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milesbeverley
2008-09-24, 10:01
Ever since I bought the Squeezebox Duet I have had problems playing the standard Apple .M4A files without the audio stuttering. I fund a post on this forum explaining how to change the config file to add the FAAD program to play MOV files. Everything worked fine (with only minor stuttering) until this morning...

I installed the k-lite codec pack which asked to uninstall a number of seemingly duplicate codecs on my Vista system. Then there was no audio from the Squeezebox. I assumed it need to have Quicktime reinstalled so I uninstalled itunes and reinstalled the latest version. The stuttering audio is back. I then updated the config file again however this time the stuttering audio continues. It doesn't start immediately but when it does it keeps stuttering. I have tried rebooting etc but nothing helps.

As the Squeezebox has been around for a while now has anymore figured out a solid fix for the stuttering .M4A files? Help would be greatly appreciated!

peter
2008-09-24, 10:33
milesbeverley wrote:
> Ever since I bought the Squeezebox Duet I have had problems playing the
> standard Apple .M4A files without the audio stuttering. I fund a post
> on this forum explaining how to change the config file to add the FAAD
> program to play MOV files. Everything worked fine (with only minor
> stuttering) until this morning...
>
> I installed the k-lite codec pack which asked to uninstall a number of
> seemingly duplicate codecs on my Vista system. Then there was no audio
> from the Squeezebox. I assumed it need to have Quicktime reinstalled so
> I uninstalled itunes and reinstalled the latest version. The stuttering
> audio is back. I then updated the config file again however this time
> the stuttering audio continues. It doesn't start immediately but when
> it does it keeps stuttering. I have tried rebooting etc but nothing
> helps.
>
> As the Squeezebox has been around for a while now has anymore figured
> out a solid fix for the stuttering .M4A files? Help would be greatly
> appreciated!
>

Are you sure this isn't just another wireless bandwidth issue? The m4a
files are probably lossless and use a lot more bandwidth than mp3.

Regards,
Peter

bpa
2008-09-24, 12:29
faad does not use any other files - it doesn't matter what codecs you have installed. The same source code faad works on Windows, OSX and Linux.

The new instance of stuttering is probably another problem.

milesbeverley
2008-09-25, 04:24
I should have mentioned before that these files were all encoded to AAC 128k using the Apple encoder. So they are half the size of the MP3 files.

bpa
2008-09-25, 04:34
The AAC files will be decoded on the server and then, if using defasult settings, sent as Flac to SB - so you need bandwidth of about 1500kbps between server and player.

volpone
2008-09-25, 04:58
The AAC files will be decoded on the server and then, if using defasult settings, sent as Flac to SB - so you need bandwidth of about 1500kbps between server and player.

bpa, please could you confirm same bandwith is needed when using the following custom-convert.conf settings ? see this thread: http://forums.slimdevices.com/showthread.php?t=52949&referrerid=16531
Thank's in advance

Volpone



#mov mp3 * *
[mplayer-stdout] -really-quiet -vc null -vo null -cache 128 -af volume=0,resample=44100:0:1,channels=2 -ao pcm:nowaveheader:file=- $FILE$ 2>/dev/null | [lame] --silent -r -x -q $QUALITY$ -b $BITRATE$ - - 2>/dev/null
mov flc * *
[mplayer-stdout] -really-quiet -vc null -vo null -cache 128 -af volume=0,resample=44100:0:1,channels=2 -ao pcm:nowaveheader:file=- $FILE$ 2>/dev/null | [flac] -cs --endian=little --channels=2 --sign=signed --bps=16 --sample-rate=44100 --compression-level-0 - - 2>/dev/null
mov wav * *
[mplayer-stdout] -really-quiet -vc null -vo null -cache 128 -af volume=0,resample=44100:0:1,channels=2 -ao pcm:waveheader:file=- $FILE$ 2>/dev/null

bpa
2008-09-25, 14:54
Any format which is not native (i.e. not Flac, MP3, WMA, Wav) has to be transcoded into one of the native format of WAV, Flac or MP3.

If transcoding is into Flac, then no matter what the encoding rate (e.g. 32kbps, 320kbps) of the source - the Flac stream from server to player will always require about the same bandwidth about 1500kbps.

If the transcoding is into MP3 then the user may be able to select the quality and bitrate of the MP3 bitstream sent between server and player. If a user wants to limit bandwidth to a plauyer then setting the "Bit rate limit" will automatically choose the MP3 forma.

Typically for NAS systems with low power CPUs there is a compromise between bandwidth and CPU utilisation. If stuttering is happening on a NAS system with transcoded streams - two possible cause include - lack of bandwidth or CPU overload. Many NAS systems have a CPU which do not support Floating point and can suffer from CPU overload if the decoding (e.g. mplayer) and encoding applications (e.g. flac, lame) are not compiled to use Fixed point arithmetic.

Furthermore even with Fixed point the processor of a NAS system may not have enough memory or CPU capacity to handle multiple or synced streams.

volpone
2008-09-26, 10:25
Any format which is not native (i.e. not Flac, MP3, WMA, Wav) has to be transcoded into one of the native format of WAV, Flac or MP3.

If transcoding is into Flac, then no matter what the encoding rate (e.g. 32kbps, 320kbps) of the source - the Flac stream from server to player will always require about the same bandwidth about 1500kbps.

If the transcoding is into MP3 then the user may be able to select the quality and bitrate of the MP3 bitstream sent between server and player. If a user wants to limit bandwidth to a plauyer then setting the "Bit rate limit" will automatically choose the MP3 forma.

Typically for NAS systems with low power CPUs there is a compromise between bandwidth and CPU utilisation. If stuttering is happening on a NAS system with transcoded streams - two possible cause include - lack of bandwidth or CPU overload. Many NAS systems have a CPU which do not support Floating point and can suffer from CPU overload if the decoding (e.g. mplayer) and encoding applications (e.g. flac, lame) are not compiled to use Fixed point arithmetic.

Furthermore even with Fixed point the processor of a NAS system may not have enough memory or CPU capacity to handle multiple or synced streams.

Thank you very much bpa.

=> Streaming as FLAC on a single player is OK.

=> Steaming as FLAC when synching several players is "choppy" at the begining of each tracks . Is it a bandwith limit or a CPU/Mem issue ?

=> Using "Bit rate limit" (lame) option seems to cause CPU overload (my hardware is a 500 Mhz CPU NAS).

I'm not understanding well the SC settings > advanced > format UI, see screen capture.
- Why AIFF and MP3 type are greyed ?
- How to choose between format types ?

Thank's in adavance

Volpone

bpa
2008-09-26, 12:39
To get CPU and memeory usage "top" is the usual tools but I don't know if it is available for your NAS.

If items are greyed out in Settings/Filetypes then it is either
a. There is no rule in convert.conf or custom-convert.conf
b. The applications specified in the rules in convert.conf or custom-convert.conf could not be found.


In your case - the excerpt from convert.conf
1. There is no AIFF rule
2. Your MP3 rule is commented out.

AIFF is irrelevant in this case as it is effectively the same as WAV.

volpone
2008-09-29, 12:15
To get CPU and memeory usage "top" is the usual tools but I don't know if it is available for your NAS.

If items are greyed out in Settings/Filetypes then it is either
a. There is no rule in convert.conf or custom-convert.conf
b. The applications specified in the rules in convert.conf or custom-convert.conf could not be found.


In your case - the excerpt from convert.conf
1. There is no AIFF rule
2. Your MP3 rule is commented out.

AIFF is irrelevant in this case as it is effectively the same as WAV.

Thank you bpa.

Transcoding AAC to FLAC is the best compromise with my configuration (more bandwith consumption but less NAS ressources used). That's works quite well except when several players are synched (sometimes sounds "choppy" at the beginning of a track).

Last question, is there some benefits using FAAD vs MPLayer to transcode ?

Regards

Volpone

bpa
2008-09-29, 15:47
Bot FAAD and MPlayer use the same libraries so there should be no difference in the quality of audio decode.

FAAD only decodes AAC so it is much smaller and possibly more efficient but there is minimal maintenance.

MPlayer is a swiss army knife application - it can handle lots of codecs and transport as well as video so it is much bigger. IT has ongoing development so it is well maintained.

In terms of resources FAAD is the better choice - it should use less memeory and be quicker to start up.

MPlayer may be useful for users who also use ALienBBC, AACplus and possible WMA support for Softsqueeze. Some users prefer just to have one app as it minimises support issues.

milesbeverley
2008-10-06, 09:42
I have now installed the LAME.exe application as specified in the threads however the music still stutters. I have also set the bandwidth limit to 128kps but no improvement. Does anybody have any other suggestions as my Squeezebox installation is practically useless at the moment?

-Miles

bpa
2008-10-06, 09:57
What are the current FileType settings for MOV ?

milesbeverley
2008-10-06, 09:58
just a quick addition : the music files seem to play ok for less than 5 secs then they stutter. I have used the latest LAME.exe ( from http://www.rarewares.org/mp3.php) and BIt rate limited the files to 128k. I am running a fast dual core PC with plenty of memory....and it isn't running any other intensive processes. It should be capable of converting the AAC files for streaming!

milesbeverley
2008-10-06, 10:16
I just noticed that I didn't copy the Lame .dll in to the win direcory. Have now done that and rebooted. No difference.

Ok settings for are

AIF = mov123
flac = mov123/flac
MP3 = mov123/lame

I have attached my config file for your attention.

Thanks, BPA.

Phil Leigh
2008-10-06, 10:22
run the server health tests and report back (help icon bottom left of home page)

bpa
2008-10-06, 11:04
In your first post you said you had no problem once you changed from mov123 to FAAD. Your Filetypes settings shows you are back using mov123.

Try using FAAD again as there is no sign of it in the convert file.

Previoulsy did you use the custom-convert.conf file I posted in another thread ?

what_to_buy
2008-10-06, 11:14
This may not be relevant at all, but I went through a similar process dealing with stuttering. Once I switched to ethernet powerline adapters, everything was perfect (it started out as a codec issue but wasn't totally resolved until I also took care of the connection). Could be a worth a try. Good luck!

TrainedMonkey
2008-10-06, 18:39
i bought a squeezebox duet and installed squeezecenter on an old powerbook g4 (550MHz) running mac os x 10.5.x, all files are ALAC-encoded (apple lossless) and housed on an external 1TB hard drive connected via firewire 400 (fastest connection the powerbook has). the powerbook is connected via gig-e to a linksys gig-e switch. the receiver piece of the duet is connected to the linksys switch as well, but of course the receiver is only 100Mb capable.

when i first received the duet, i installed squeezecenter 7.0 on the powerbook and everything was happy. squeezecenter 7.1 came out and i installed it. that's when the stuttering started. a few seconds of the track play, then it goes silent, one or two seconds later, it starts playing again. i removed 7.1 and reinstalled 7.0 and the receiver reloaded its firmware. the stuttering continued, but then the "magic moment" happened ... the firmware on the controller (aka the remote) was updated and after it rebooted, the stuttering was GONE (back to happy times).

in the meantime, i had purchased a readynas NV+ (upgraded to 1GB ram and 4 x 500GB disks). i tried both SC 7.1 and SC 7.2 (very recently released) on the readynas and both exhibit the start of track stuttering problem.

i haven't tried SC 7.2 on the powerbook yet, but i'm guessing it will exhibit the same stuttering issue. it seems to be related to the controller software in my case and i'm really hoping it can be fixed so i can use my readynas (main reason i purchased it was to have it serve my music library).

the reason i went with ALAC instead of FLAC is because i don't want to duplicate my music library (i already use itunes for my ipod and will for an iphone in the future). it would be REALLY cool if logitech allowed you to load the squeezebox with whatever codecs you wanted (as i only use ALAC). perhaps it's a licensing issue?

thanks in advance for any help in resolving my issue (for now i'm back to SC 7.0 running on my old dinosaur powerbook serving my music).

milesbeverley
2008-10-07, 02:02
I have usedhealth test. At 128kps everything is above 100%. At 320kps this is the graph.

< 10 : 0 : 0%
< 20 : 0 : 0%
< 30 : 0 : 0%
< 40 : 0 : 0%
< 50 : 0 : 0%
< 60 : 0 : 0%
< 70 : 1 : 1%
< 80 : 0 : 0%
< 90 : 5 : 3% #
< 95 : 6 : 4% ##
< 100 : 4 : 3% #
>=100 : 130 : 89% ############################################
max : 100.000000
min : 64.102564
avg : 98.876449

BPA : I originally used FAAD and the problem wwent away 90% of the time. SOmething changed on my system (i presumed it was the codecs I downloaded) and the stuttering came back with FAAD as well. I have now tried LAME (as instructed by Logitech on their help pages) but the stuttering continues. Can you please send me the link to the custom convert file so I can use that instead of always updating the original convert file. Thanks.

bpa
2008-10-07, 02:26
This post has the instruction for using FAAD instead of mov123. Just do stesp 3 & 4 as I think you already have done steps 1 & 2.

http://forums.slimdevices.com/showpost.php?p=329123&postcount=4

The benefit of using custom-convert.conf means to revert to mov123 just delete (or rename) the custom-convert.conf file and restart SC. Makes it easy to do comparison tests.

milesbeverley
2008-10-07, 03:16
I have followed you're instructions. The sound doesn't stutter but there is bad hiss (like tape hiss) over the music and also the internet radio. Have you come across this problem before?

milesbeverley
2008-10-07, 03:18
and i can confirm that the AAC file types look like:

Flac = Faad/flac
mp3 = faad/lame
wav = faad

milesbeverley
2008-10-07, 03:28
I have played round with the bit rate limit and seen different things happen. The hiss seems to occur at 160kps. I then set the bit rate limit to 128kps (as my .m4a files are 128k). The music starts well (no hiis and no stutte) but then after 30 seconds it starts to stutter. I then tried another music file and the hiss comes back even at 128k limit. When I set the bit rate limit = No limit then the file plays for 5 seconds then stutters (no hiss). Hope this helps you figure out what is wrong??

milesbeverley
2008-10-07, 03:38
This is the output from the 128k network test.

< 10 : 0 : 0%
< 20 : 0 : 0%
< 30 : 0 : 0%
< 40 : 0 : 0%
< 50 : 0 : 0%
< 60 : 0 : 0%
< 70 : 0 : 0%
< 80 : 0 : 0%
< 90 : 0 : 0%
< 95 : 0 : 0%
< 100 : 0 : 0%
>=100 : 21 :100% ##################################################
max : 100.000000
min : 100.000000
avg : 100.000000


I have now switched on the performance monitoring and it shows this:

The server is currently collecting performance statistics for this player.

You may set warning thresholds for each measurement. Events which exceed this threshold will be logged to a log file. The log is stored at: C:\ProgramData\SqueezeCenter\Logs\perfmon.log
Signal Strength
This graph shows the strength of the wireless signal received by your player. Higher signal strength is better. The player reports signal strength while it is playing.
< 10 : 0 : 0%
< 20 : 12 : 14% ######
< 30 : 48 : 56% ###########################
< 40 : 4 : 5% ##
< 50 : 22 : 26% ############
< 60 : 0 : 0%
< 70 : 0 : 0%
< 80 : 0 : 0%
< 90 : 0 : 0%
< 100 : 0 : 0%
>=100 : 0 : 0%
max : 44.000000
min : 16.000000
avg : 27.906977

Control Connection
This graph shows the number of messages queued up to send to the player over the control connection. A measurement is taken every time a new message is sent to the player. Values above 1-2 indicate potential network congestion or that the player has become disconnected.
< 1 : 3483 :100% ##################################################
< 2 : 0 : 0%
< 5 : 0 : 0%
< 10 : 0 : 0%
< 20 : 0 : 0%
>=20 : 0 : 0%
max : 0.000000
min : 0.000000
avg : 0.000000

It seems that the player shows a lower signal strength. Which is strange as I have an airport express sitting right by the player.

milesbeverley
2008-10-07, 05:20
I have now boosted the signal strength by moving the aiport express around and switching on interference robustness on the aiport. the singal strength test looks like this now.

Signal Strength
This graph shows the strength of the wireless signal received by your player. Higher signal strength is better. The player reports signal strength while it is playing.
< 10 : 0 : 0%
< 20 : 0 : 0%
< 30 : 0 : 0%
< 40 : 0 : 0%
< 50 : 0 : 0%
< 60 : 0 : 0%
< 70 : 0 : 0%
< 80 : 44 : 49% ########################
< 90 : 43 : 48% #######################
< 100 : 3 : 3% #
>=100 : 0 : 0%
max : 90.000000
min : 75.000000
avg : 82.311111

milesbeverley
2008-10-07, 05:24
I am now getting buffer fullness warnings.

Buffer Fullness
This graph shows the fill of the player's buffer. Higher buffer fullness is better. Note the buffer is only filled while the player is playing tracks.
Squeezebox1 uses a small buffer and it is expected to stay full while playing. If this value drops to 0 it will result in audio dropouts. This is likely to be due to network problems.

Squeezebox2/3 uses a large buffer. This drains to 0 at the end of each track and then refills for the next track. You should only be concerned if the buffer fill is not high for the majority of the time a track is playing.

Playing remote streams can lead to low buffer fill as the player needs to wait for data from the remote server. This is not a cause for concern.

< 10 : 122 :100% ##################################################
< 20 : 0 : 0%
< 30 : 0 : 0%
< 40 : 0 : 0%
< 50 : 0 : 0%
< 60 : 0 : 0%
< 70 : 0 : 0%
< 80 : 0 : 0%
< 90 : 0 : 0%
< 100 : 0 : 0%
>=100 : 0 : 0%
max : 8.274206
min : 0.000000
avg : 0.435097

is this something to do with the problem?

Phil Leigh
2008-10-07, 08:44
I am now getting buffer fullness warnings.

Buffer Fullness
This graph shows the fill of the player's buffer. Higher buffer fullness is better. Note the buffer is only filled while the player is playing tracks.
Squeezebox1 uses a small buffer and it is expected to stay full while playing. If this value drops to 0 it will result in audio dropouts. This is likely to be due to network problems.

Squeezebox2/3 uses a large buffer. This drains to 0 at the end of each track and then refills for the next track. You should only be concerned if the buffer fill is not high for the majority of the time a track is playing.

Playing remote streams can lead to low buffer fill as the player needs to wait for data from the remote server. This is not a cause for concern.

< 10 : 122 :100% ##################################################
< 20 : 0 : 0%
< 30 : 0 : 0%
< 40 : 0 : 0%
< 50 : 0 : 0%
< 60 : 0 : 0%
< 70 : 0 : 0%
< 80 : 0 : 0%
< 90 : 0 : 0%
< 100 : 0 : 0%
>=100 : 0 : 0%
max : 8.274206
min : 0.000000
avg : 0.435097

is this something to do with the problem?


Absolutely - this is the evidence of stuttering(apart from the fact you can hear it!)...the buffer needs to remain pretty much full most of the time, except at teh beginnign and end of songs - yours is mostly empty!.

Also, before you fixed it, your wireless strength was no good - so you had two problems - now you have one (the buffer fullness).

Now you need a Mac expert to help you - the only time I had this (on XP) it was a bizarre IP/Mac address conflict. You might want to check that the MAC address of your slim device (as shown in the settings on th eplayer itself) do indeed correspond to the label on the bottom - and also that you don't have an IP conflict. If possible, set the server to use static IP.

milesbeverley
2008-10-07, 08:50
Phil, thank you for your response. I can see the MAC address written on the bottom of the recivers...how do I check this with the assigned MAC address? Also how do I check for IP conflicts and then dcide which IP address to set to static? Sorry for the basic questions but I'm not a network specialist and I presumed that all this should have worked from the box.

regards,

Miles

milesbeverley
2008-10-07, 08:52
oh, I should have added that I am running the Swueezebox service on a VISTA Home PC.

milesbeverley
2008-10-07, 09:07
I checked the MAC addresses and they match. The player (as I have two players) report a 88% wireless singal strength. Still the buffer is less than 10%. On my other player the buffer is 100% but that is probably because it is near the PC with the SqueezeCenter installed (and router).

BTW, the firmware is reported as 47 on the player. Is that the latest firmware?

milesbeverley
2008-10-07, 09:42
I also changed the router channel number but that didn't have any effect.

milesbeverley
2008-10-07, 09:49
I now moved the receiver to sit beside the PC and router. Singal strength didn't change but buffer fullness went upto 100%. I moved it back to my bedroom...signal strength was very good at 90% but buffer fullness went down to less than 10%!!! This seems to be confusing. Why would the signal strength be good but the buffer can't fill up quick enough?? Unless the files are still being transferred as large files and aren't really encoded to a smaller stream???

Phil Leigh
2008-10-07, 10:34
Well that's odd...normally a very bad wireless signal will prevent the buffer filling... but it seemed you had fixed the wireless strength issue - or maybe not!

There really isn't much difference between WS of 90 vs 100...
It seems to me there must be another mechanism at play.

Do you have any anti-virus running? (just a thought).
Can you plug in an ethernet cable temporarily to eliminate the wi-fi as an issue?
If Buffer fullness is fine when wired, that does narrow the problem down quite a bit...

milesbeverley
2008-10-07, 10:54
I have Zone Alarm running. I have already tried the connection when Zonealarm is switched off and it doesn't make any difference. It will be difficult to connect an ethernet cable as the Squeezecenter is running on a Tower PC Vista. If I move the receiver to the PC then it is the same as using the wifi....it will give a 100% buffer fullness. It does seem to be the wifi connection in some way....if I move the receiver further away the buffer fullness decreases.

For my current setup I use a time capsule router with an airport express to extend the network. The receiver with the problems sits next to the airport express. The Vista running the Squeezecenter is sitting near the time capsule. The airport is boosting the signal. I will try turning off the airport express and see if that helps but the signal strength will presumably drop.

bpa
2008-10-07, 16:54
I think you have have three problems.

1. Vista and m4a stuttering when using mov123. This is well documented and changing from mov123 to faad eliminates the stuttering.

2. Stuttering due to wireless. It sounds like your wireless extender is muddying the issue. - if the extender has a poor link back to server but is close to SB - you will get high wireless signal but poor throughput.

Also the propagation from a simple dipole antenna is doughnut shaped so immediately besides a AP may not give the optimum signal. I think extender can reduce throughtput of the wireless network overall.

I suggest testing wired to router or at least just have a single wireless stations and an SB 3-4m away from it.

3. Will you check the version of faad you have installed. I found that there is a background hiss when faad 2.0 is used but there is no hiss when version 2.6 is used.

milesbeverley
2008-10-08, 01:56
In answer to your questions:

1+3) I am now using Faad 2.6.1.

2) Are you suggesting that I test the SB3 with a wired connection to the router? I can do that but I have already proved that the buffer fullness increases when the SB3 is near the PC. The reason I bought the Duet was to distribute music around my apartment. If it can't even stream music to a bedroom which is 5 metres away (even with an extender) then it isn't doing the job that I bought it for. As you can see this is becoming very frustrating as it should work out of the box.

Now the SqueezeCenter has crashed my PC and after rebooting it has lost all my settings. So when starting the SC Iam asked to go through the setup assistant again. Is there another way around this or do I need to setup everything again??

Is there another way to set the extender (or network) to increase the bandwidth for streaming?

I will also test the connection for stuttering without the extender and see if that improves things.

bpa
2008-10-08, 03:00
1+3) I am now using Faad 2.6.1.


Can you confirm you still have hiss with 2.6.1 ?
If you have hiss, it's possible the m4a's have some new encoding and FAAD hasn't been updated. What version of iTunes did you use to create the m4a's or when were they created ?

If you have hgiss with 2.6.1, I'll post later today some example command line to convert your m4a into mp3 so that the converted mp3's can be tested in WMP to confirm the "hiss" is in the file conversion and not SB playback. Last night I did some m4a to mp3 tests and Faad 2.0 had hiss but 2.6.1 had none.




2) Are you suggesting that I test the SB3 with a wired connection to the router? I can do that but I have already proved that the buffer fullness increases when the SB3 is near the PC.

A test without wireless would check whether there is any residual stuttering due to faad. You need to ensure that stuttering is now purely wireless in origin. If there are 2 sources of stuttering then the non-wireless source must be eliminated first otherwise any wireless testing is uncertain.



The reason I bought the Duet was to distribute music around my apartment. If it can't even stream music to a bedroom which is 5 metres away (even with an extender) then it isn't doing the job that I bought it for. As you can see this is becoming very frustrating as it should work out of the box.

Understandable but local environment can affect wireless - such a thick walls or internal wall insulation which has metal foil.



Now the SqueezeCenter has crashed my PC and after rebooting it has lost all my settings. So when starting the SC Iam asked to go through the setup assistant again. Is there another way around this or do I need to setup everything again??

I am bit sceptical that SC has crashed Vista. The settings are kept in the prefs directory. If the server settings are there then you should be able to restart.



Is there another way to set the extender (or network) to increase the bandwidth for streaming?

Rather than use an extender - you could use a Homeplug network connection between router and SB or to set up an AP (with separate ssid) closer to the SB. I use this solution in a room which is foil insulated an distant from main router.

dcote
2008-10-08, 04:04
here are a few cents of mine:

i ran my SC7 on windows 2003 server on a really resource-starved 700MHz PIII - equivalent with 1GB RAM (a VIA ITX system). playing apple worked just fine (even with mov123) *unless* my server was busy doing something else. symptoms:

playing an apple track the first time took about 20-25 seconds to commence
playback started then stuttered or stopped after some seconds
good wlan signal (40-60%)
network diagnostics showed nothing untoward
buffer dropping to zero

i discovered my server was sometimes so busy that it could not decode apple and re-code to FLAC fast enough. (i used the windows performance monitor for this). using mov123, my via cpu would clock in at about 40% (!) cpu usage to decode aac and re-code to flac...

i changed the transcoding settings to output WAV, which reduced the cpu cycles enough (to about 30%) to provide a reasonably steady stream *most* of the time.

other times, i just had to shut down some cpu/ram hogging apps (emule was the worst, keeping the web-UI open second!) to make it work properly.

does your vista machine seem sluggish sometimes?
and did you try connecting through a wire? if that works fine, you obviously have a WLAN problem. if not, you have a server problem.

milesbeverley
2008-10-08, 04:42
The preference files were there but for some reason I still had to go through the setup process again.

I am currently using Faad 2.6.1 (just downloaded ysterday). The hiiss only occurs when I set a bandwidth limit. Maybe it is the low compression which causes the hiss. I used iTunes to create my .m4a files. The latest version (8.01) was used to create some music files which I have tested.

Playing the SB receiver in wired mode (to the router) the buffer fullness is 100% and there is no stuttering. Next test was check the SB receiver without the wired connection (wireless) near to the router. When selecting the player the controller showed me two receivers both with the same code (one had upper case the other lower). Strange...So wireless and next to the router gives no stuttering and 100% bufferfullness.

I even tried connecting an ethernet cable from the airport express to the SB receiver in the bedroom but still stuttering and <10% buffer fullness.

Ok. is there anything else I can try or do I need to purchase this extra Homeplug kit to get the SB receiver working? Is it easy to setup the Homeplug kit and can it extend my current network or does it create a separate network? You also mention setting up an AP. Do you mean Access Point? Can I use my Aiport Express to do this? If I have another ssid (network name) how can the SB Center stream music to two SB receivers both sitting on two different networks? I am not a network expert so before I start to buy anymore equipment I need to understand how this can all be configured to work together.

milesbeverley
2008-10-08, 04:48
does your vista machine seem sluggish sometimes?
and did you try connecting through a wire? if that works fine, you obviously have a WLAN problem. if not, you have a server problem.



Dcote : The PC doesn't seem sluggish. I checked the CPU usage and it varies between 5% and 15% when playing an .m4a file. It seems to be a WLAN problem.

bpa
2008-10-08, 05:22
Before offering any network advice - please describe the network topology in detail and the connected equipment.

This should include:

What is the hardware in the network (I.e. PC, router, NAS, Time Capsule, switches/hubs, any other network equipment).

How are the equipment connected (e.g. wired/wireless from PC to router, wired/wireless from router to extender, wired/wireless Time Capsule to ?)

How is extender confgigured WDS or other ?
IS the SSID of extender the same as the wireless router ?
Can you tell whether SB connects wirelessly to extender or router ?

Static network addresses or DHCP ?

milesbeverley
2008-10-08, 05:51
BPA : This should include:

What is the hardware in the network (I.e. PC, router, NAS, Time Capsule, switches/hubs, any other network equipment).

How are the equipment connected (e.g. wired/wireless from PC to router, wired/wireless from router to extender, wired/wireless Time Capsule to ?)

Answer : The modem is wired to the Time Capsule. The time capsuule acts as a Router. The Time Capsule is wired to the PC running Vista Home. I use an Aiport Express as an Extender (select extended network under Airport settings). The extender is placed about 10-15m away from the router in another room. The Extender is connected wirelessly to the Router. I have 2 SB receivers. 1 receiver is next to the Pc and about 4m away from the router. This receiver works fine. The other receiver is about 1.5m away (and I have tested 3m away) from the extender in the bedroom.

How is extender confgigured WDS or other ?
IS the SSID of extender the same as the wireless router ?
Can you tell whether SB connects wirelessly to extender or router ?

Answer: The extender is configured as "Extend Network". The other options I could use are 1) Create a wireless network, 2) participate in a WDS network, 3) join a wireless network. The extender and Router both use the same Network name (ssid). The extender is setup to use DHCP.

For the time capsule the radio mode is 802.11n (b/g compatible). The time capsule also uses DHCP.


Static network addresses or DHCP ?

bpa
2008-10-08, 14:00
To investigate the "hiss" issue using WMP as a player and also varying quality settings and bitrates.

To convert an m4a files into mp3 using faad, use the following commands issues from a command prompt.

The following command converts the file test.m4a into a raw WAV file test.wav.
faad -w -f2 test.m4a >test.wav

The following command converts the raw WAV file test.wav into an MP3 file test.mp3
lame --resample 44100 -q 2 -b 320 -x -r test.wav test.mp3

The option after "-q" is the quality of compression (1=slow good, 9=fast,poor) and the values after "-b" is the bit rate.

You can also compare against the standard SC conversion using mov123
The following command converts the file test.m4a into a raw WAV file test.wav using mov123.
mov123 test.m4a >test.wav

The WAV->MP3 conversion is similar but I think you need to omit the "-x"
lame --resample 44100 -q 2 -b 320 -r test.wav test.mp3

bpa
2008-10-08, 14:35
Regarding your network.

First - a quick answer about Homeplug. A pair of Homeplug adaptors will act as an Ethernet cable. They usually require no configuration and are usually invisible to the connected devcies. The speed can vary between from about 70mbps to 2mbps depending on the "quality" of your wiring and whether the sockets there are many circuits between the sockets being used for Homeplug.

Assuming the Time Capsule-Airport Express wireless link is a "weakpoint" in your network and/or the WDS functionality is reducing bandwdith, the solution may be to connect Time Capsule-Airport Express with a wired connection either Ethernet or Homeplug. Once wired, you then have a choice to still use WDS or to set Airport Express as an Access point. Airport Express using WDS may still have bandwidth reduction issues but Access point may have interference issues if there is overlap in the coverage between Time Capsule and Airport Express.

Given that there is no ideal solution, it may be worthwhile considering why you found the need to use an extender in the first place.

Just looking at Apple website - neither Time Capsule nor Airport Express have external antenna, however the TC uses 802.11n.

There also seems to be discussions ( http://forums.macrumors.com/showthread.php?t=448450 ) that the TC may not be the best choice as the main wireless router.

Unless you have very solid walls, I wonder whether a single router with external antenna (probably extended range antenna) might provide adequate coverage.

milesbeverley
2008-10-09, 06:53
Problem has been solved!!!!

I took the plunge and bought a sitecom 200mps homeplug package. It cost me 125 euros. Yes, I could have bought acheaper one but I wanted to make sure that it worked properly and was supported. I initially plugged one into the time capsule and the other into the airport express. The airport couldn't work with it in that configuration. No wifi computer could access the airport. I think the ethernet port on the aiport is only meant for computers, printers etc. The time capsule will only connect to the airport wirelessly.

So instead I plugged the homeplug direectly into the SB receiver, selected ethernet conectioo on the handset and everything worked first time. No stutter. After testing the buffer fullness I now get 100% whereas before I was only getting <10%.

Thank you again for your help BPA. The homeplug did seem to be the best and simplest option. I should have used that instead of buying an airport express.

I won't test the hiss as this only occurred when I changed the bit rate...now that everything is working I will leave it as it is.