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Horizons
2006-04-02, 11:19
I have an SB3 used wirelessly with a Linksys WRT54G router. I just moved last week and re-setup everything. I am currently using no encrytion until I can get the SB3 working perfectly. I can now connect but playback starts for a few seconds and then is breaking up thereafter.

Is there a buffer setting or ? that would fix this? Can anyone tell me some hints to troubleshoot this audio breaking up problem? Something tells me this is fairly common with an easy setting fix but a search hasn't come up with anything.

Many thanks in advance!

Mark Lanctot
2006-04-02, 11:43
Sounds like you're experiencing poor wireless bandwidth issues. What file type are you playing?

Check here:

http://wiki.slimdevices.com/index.cgi?NetworkProblemsSecondGuide

for possible solutions. Hopefully changing wireless channels is all that's required. If all else fails, play back lossless files or high-bitrate MP3 at a lower bitrate, see SlimServer Player Settings - Audio - Bitrate Limiting.

Horizons
2006-04-04, 09:33
Sounds like you're experiencing poor wireless bandwidth issues. What file type are you playing?

Check here:

http://wiki.slimdevices.com/index.cgi?NetworkProblemsSecondGuide

for possible solutions. Hopefully changing wireless channels is all that's required. If all else fails, play back lossless files or high-bitrate MP3 at a lower bitrate, see SlimServer Player Settings - Audio - Bitrate Limiting.

Thanks for the response. I am playing Apple Lossless. The funny thing is one day everything will work perfectly and the next day all I get is constant audio breakup. I would hate to go to a lossy file format after ripping 650 CDs to Apple lossless.

Is this a common problem?

TIA

abdomen
2006-04-04, 09:46
Thanks for the response. I am playing Apple Lossless. The funny thing is one day everything will work perfectly and the next day all I get is constant audio breakup. I would hate to go to a lossy file format after ripping 650 CDs to Apple lossless.

Is this a common problem?

TIA
Wireless interference in the bands 802.11b and g operate in is extremely common. Fortunately, most folks using 802.11g and the SB2/3 with losslessly compressed files are able to resolve such issues, often just by changing the channel on the access point. Mark has pointed you in the right direction; post again to indicate whether any of those things do the trick.

Ross L
2006-04-04, 10:59
You might want to consider trying out netstumbler. Wireless sniffing will tell you what channels your neighboring networks are on, then you can choose 1/6/11 based on which channel is least interfered with.

Horizons
2006-04-04, 11:22
Sounds like you're experiencing poor wireless bandwidth issues. What file type are you playing?

Check here:

http://wiki.slimdevices.com/index.cgi?NetworkProblemsSecondGuide

for possible solutions. Hopefully changing wireless channels is all that's required. If all else fails, play back lossless files or high-bitrate MP3 at a lower bitrate, see SlimServer Player Settings - Audio - Bitrate Limiting.

I'm sorry to sound dense but how do you change wireless channels? I have searched and can't find it or I don't see these options on my slimserver SW interface.

Thanks.

kdf
2006-04-04, 11:30
Quoting Horizons <Horizons.25r5jn1144175102 (AT) no-mx (DOT) forums.slimdevices.com>:
> I'm sorry to sound dense but how do you change wireless channels?

it would be a setting on your router (often they have a web interface
to their settings). squeezebox will find the channel when it tries to
find the wireless network on power up.
-k

Kyle
2006-04-04, 11:35
You change channels on your wireless router interface. Check your router instruction manual.

Ross L
2006-04-04, 11:36
You need to login to your linksys router via the web interface for the router. Your wireless router/AP selects which channel it broadcasts on.

If you'd like, you can call me and I'll walk you through it. Please see my sig for the number.

EDIT: Kyle=quicker than Ross!

abdomen
2006-04-04, 11:41
I'm sorry to sound dense but how do you change wireless channels? I have searched and can't find it or I don't see these options on my slimserver SW interface.

Thanks.
It's done on the router. See your WRT54G documentation (or the Linksys website).
EDIT: Abdomen is the slowest of all!

Mark Lanctot
2006-04-04, 11:46
Dang, I'm the slowest of all, but I was doing some work at the time.

All I have to add by now is:

If you don't know your router IP address, it's likely you've never gone in to change it, so it's safe to assume it's at factory default. It would be 192.168.1.1 if you have a Linksys router, 192.168.1.0 for D-Link, Netgear and others, and 192.168.2.1 for SMC. Just enter these addresses into your browser URL to try them out and see if you get a box asking you for user name and password.

User name and password should be in your router documentation, or check here:

http://www.phenoelit.de/dpl/dpl.html

Horizons
2006-04-04, 11:50
You guys are all pretty fast IMHO.

Thanks for the info, I will check the Linksys router settings first thing tonight.

StadiumBlitzer
2006-04-10, 12:47
I am working through the same issues described at the start of this thread with continuous drops/interruptions, but I'm having trouble finding a new channel. I installed NetStumbler and was surprised when it found 14 other wireless routers in my neighborhood spread fairly evenly across channels 1/6/11. I know these are non-overlapping channels, but since they're so crowded does it make sense to try one in between or am I asking for trouble later? For example, I tried 3 and it was a slight improvement but still not acceptable. Also, is there a way to evaluate the traffic on 1/6/11 and determine which one is the best choice? Thanks.

Mark Lanctot
2006-04-10, 13:00
It's best to get NetStumbler graphing your connection as you switch channels.

It isn't very intuitive to get this up and running - what you have to do is isolate your connection on the left-hand pane so it's the only one appearing in a category (this is easiest to do when sorting by SSID), then double-click it. You'll get a strength graph.

Keep the graph going and change channels - you should see some fairly dramatic changes. You're looking not only for the channel that gives you greatest strength, but also one that's the most stable.

I remember reading a link on Tom's Networking to a paper describing in extremely technical/mathematical terms that there were other non-overlapping channels which include 4 and 8, but I can't find that article right now. I'll dig it up tonight. I ended up using channel 8 as it was the highest and most stable by the graphing I mentioned above.

Mark Lanctot
2006-04-10, 14:17
Found the link I was looking for.

It's from:

http://www.tomsnetworking.com/2004/02/28/how_to/page3.html

which is a good article to read on its own regarding these issues - it ain't just the Squeezebox with these problems!

It points to here:

http://www.tomsnetworking.com/FAQ-37-Performance-16.php#486

which references this paper:

http://www.cirond.com/White_Papers/FourPoint.pdf

that essentially concludes through some pretty intense mathematics that the non-overlapping channels are 1, 4, 8 and 11. 8 worked best for me, so they may have a point.

StadiumBlitzer
2006-04-11, 10:51
Thanks, Mark. The "When Wireless LANs Collide" article was particularly interesting. I was able to run the NetStumbler tests, too and channel 8 was had the best performance for me by a significant margin. The Slim performance is better, but I'm still getting bad drops and "underwater" audio. At least now I can focus on other possible causes. Thanks for your help.

Mark Lanctot
2006-04-11, 11:04
Thanks, Mark. The "When Wireless LANs Collide" article was particularly interesting. I was able to run the NetStumbler tests, too and channel 8 was had the best performance for me by a significant margin. The Slim performance is better, but I'm still getting bad drops and "underwater" audio. At least now I can focus on other possible causes. Thanks for your help.

When you're experiencing wireless bandwidth constraints, you can get dropouts - but you should not be getting distorted "underwater" audio as you describe it.

What file format are you streaming in? How did you rip these files? Do they play OK on your PC?

What did the Network Test plugin indicate?

You can try bitrate limiting as a temporary workaround, which is the last item on that Wiki entry.

StadiumBlitzer
2006-04-11, 15:05
We largely use it to stream Real audio using AlienBBC plus streaming MP3s. We also listen to stremaing radio via SquuezeNetwork.

* MP3s - the performance is always very choppy. It worked well when I first installed a couple months ago. Since then I have upgraded SlimServer to 6.2.2 and mplayer to the latest stable version after reading another post in these forums. However, it's made almost no difference (other than losing playlists, which I know is a known bug). I ripped all of the MP3s using the default settings in Windows MediaPlayer and another ripper (Ashampoo something). They are all 356K MP3s. I tried to use bitrate limiting last night and it seemed to improve things a bit, but still lots of breakups. I ran out of time to test all of the lower settings, so there may be some promise there.

In the Server Health section of the admin pages I noticed for the first time the "Occasional poor server response" message, but I wanted to do a more testing before I'm sure.

* Streaming RealAudio via BBC - works fairly well most of the time, but still often breaks up and occassionally drops completely.

* Streaming radio via SqueezeNetwork - usually rock solid for hours at a time, including today.

The performance of SqueezeNetwork makes me think the problem must be on the machine where I have SlimServer installed (my guess is that SqueezeNetwork goes straight through the router?). Since my stereo is closer to the router than the machine where the Slim Server is installed and the channel problems are so common, I thought it might be a network issue, but now I'm not so sure.

One idea I had was rolling SlimServer and mplayer back to the original versions that was working in the past. I assume I'd have to uninstall everything and then restart from scratch. Thanks again for your help.

Mark Lanctot
2006-04-11, 15:59
* MP3s - the performance is always very choppy. It worked well when I first installed a couple months ago. Since then I have upgraded SlimServer to 6.2.2 and mplayer to the latest stable version after reading another post in these forums. However, it's made almost no difference (other than losing playlists, which I know is a known bug). I ripped all of the MP3s using the default settings in Windows MediaPlayer and another ripper (Ashampoo something). They are all 356K MP3s. I tried to use bitrate limiting last night and it seemed to improve things a bit, but still lots of breakups. I ran out of time to test all of the lower settings, so there may be some promise there.

Again, sounds like very poor wireless bandwidth.

Have you tried the Network Test plugin?


* Streaming RealAudio via BBC - works fairly well most of the time, but still often breaks up and occassionally drops completely.

* Streaming radio via SqueezeNetwork - usually rock solid for hours at a time, including today.

The performance of SqueezeNetwork makes me think the problem must be on the machine where I have SlimServer installed (my guess is that SqueezeNetwork goes straight through the router?). Since my stereo is closer to the router than the machine where the Slim Server is installed and the channel problems are so common, I thought it might be a network issue, but now I'm not so sure.

Yes, you're right, SqueezeNetwork does got through your router, but the streams are much lower bitrate, usually 96 kbps - 128 kbps, so they ought to perform better if you have wireless bandwidth issues.


One idea I had was rolling SlimServer and mplayer back to the original versions that was working in the past. I assume I'd have to uninstall everything and then restart from scratch. Thanks again for your help.

Try the Network Test plugin first. If you have wireless bandwidth issues, rolling back SlimServer won't help. You have 14 wireless networks in your neighborhood - I bet there are a few very strong ones and I bet they were set up very recently.

That "underwater" audio you stated two posts ago is puzzling though. It should not be caused by wireless congestion at all. Could you elaborate a bit more on it? Is it only on one file format? Do you have file conversion enabled?

StadiumBlitzer
2006-04-13, 06:13
I tried the Net Test plugin and it appears that at 2000 kbps performance starts to drop sharply. At 1500 I get 100%/99% (there are occasional dips) and 1000 is 100/100. Regarding the Server & Network Health data, the only area that appears less than very good is Player Signal Strength, which just looks OK:
<70 6%
<80 85%
<90 9%

One possible small improvement I've noticed int he last day or so is that songs and even albums will play all the way through where earlier they would drop completely. Can you recommend any other tests to try? For example, I was thinking I could plug my player directly into my router to see if that improves things. Also, would it help to put an antenna on the player?

Mark Lanctot
2006-04-13, 06:47
I tried the Net Test plugin and it appears that at 2000 kbps performance starts to drop sharply. At 1500 I get 100%/99% (there are occasional dips) and 1000 is 100/100. Regarding the Server & Network Health data, the only area that appears less than very good is Player Signal Strength, which just looks OK:
<70 6%
<80 85%
<90 9%


Hmm...with that kind of performance you should be fine for all MP3s, OK for FLAC and probably OK for WAV as well.

The Network Test doesn't stream audio, it just refreshes the screen, so it's a simulated load though.



One possible small improvement I've noticed int he last day or so is that songs and even albums will play all the way through where earlier they would drop completely. Can you recommend any other tests to try? For example, I was thinking I could plug my player directly into my router to see if that improves things. Also, would it help to put an antenna on the player?

Plugging it directly into the router will definitely show if you have any wireless bandwidth constraints or if the problems are confined to the server.

I haven't heard of antennas being used on the SB. Obviously you'd need an SB2 for this as the SB3's antennas are internal. The SB2 seems to use an ordinary SMA connector, so most of those aftermarket high-gain antennas should be compatible.

However, most people use high-gain antennas on their router, not the client device. This is apparently a very effective solution for increasing wireless networking strength, much better than turning the transmit power up if your router firmware allows you to do so.

Your signal strength is a little bit higher than mine though, but I'd suspect with the number of wireless networks in your area it may not all be "quality" signal. A high-gain antenna on your router might be enough to out-compete the neighboring networks and enable you to win your local wireless arms race. :-)

StadiumBlitzer
2006-04-13, 11:55
OK, I plugged the player into the router and got the exact same performance. I'll give the antenna a shot and report back. Re: the wireless arms race... I found out the guy directly behind me has 3 wireless APs in his house (one each on 1/6/11). I am really beginning to think about the cost of running wires instead of relying on wireless.

Mark Lanctot
2006-04-13, 12:07
OK, I plugged the player into the router and got the exact same performance. I'll give the antenna a shot and report back.

Whoa, better not! If you're getting the same performance wired then it isn't a wireless bandwidth restriction. Look at the server: CPU load, memory usage, etc. Don't play while rescanning. Is the web interface slow on networked computers?

Could you give some details about the server? Processor, memory, OS?


Re: the wireless arms race... I found out the guy directly behind me has 3 wireless APs in his house (one each on 1/6/11). I am really beginning to think about the cost of running wires instead of relying on wireless.

Je-ee-eez. Hard to compete with that. Certainly if you can go wired that would be better.

Once you're wired you may want to get a 2.4 GHz cordless phone setup if you want a little payback. ;-)

StadiumBlitzer
2006-04-13, 17:27
I'm confused... I plugged the player into the router to eliminate wireless router to player interference as a possible cause (I didn't think that was the problem but why not eliminate as much as possible?). An antenna might still help improve the wireless router to server connection, right?

The specs on the PC: P4 2.8GHz with 1GB memory running XP Home. Very little else is running on it right now. The Dlink wireless adapter I'm using usually reports Very Good/Good connectivity, which I know may not reflect the quality of the signal required for Slim.

gblanston
2006-04-15, 23:10
I am having similar problems with FLAC. Sometimes the audio seems to actually slow down as it skips and gets hung up. I think I understand what you mean by "underwater" sound... it skips, delays, and gets garbled.

I have yet to experience the problem with typical (128-192kbs) MP3 files, but it happens all the time with FLAC, which is the only lossless format I currently use. The same files play fine directly on the PC running Slimserver.

I generally see 70-80% readings for my signal strength at the PC (which is not directly connectd to my router), and similar readings at my 2 SB3 locations. I am still running 802.11b, so I do wonder if 11b is somehow "weaker" than the many competing networks in my urban setting.

I wish I could offer something more helpful, but I wanted to at add this information to the discussion since it seems similar to your problems.

Mark Lanctot
2006-04-17, 14:08
I'm confused... I plugged the player into the router to eliminate wireless router to player interference as a possible cause (I didn't think that was the problem but why not eliminate as much as possible?).

You said that it still performed the same wired. If that's the case, you're not limited by wireless bandwidth - we've eliminated that variable. The stuttering is caused at the server itself.


An antenna might still help improve the wireless router to server connection, right?

Yes, but we've established that wireless bandwidth isn't causing the problem if you experience the same issues wired.


The specs on the PC: P4 2.8GHz with 1GB memory running XP Home. Very little else is running on it right now. The Dlink wireless adapter I'm using usually reports Very Good/Good connectivity, which I know may not reflect the quality of the signal required for Slim.

Quite similar to my setup, except I only have 512 MB of memory and a Linksys WRT54G router.

Unfortunately troubleshooting from this point is harder. We have to look for something that's causing SlimServer to bog down. Look at CPU usage, memory usage (shouldn't be a problem with 1 GB but you never know), etc. You indicate you're running the latest 6.2.2 - hopefully it's a very recent one (within the past two weeks) that includes SB firmware 37 as it's fixed a lot of problems. Also 6.2.2 has all the latest bugfixes.

Mark Lanctot
2006-04-17, 14:12
I am still running 802.11b, so I do wonder if 11b is somehow "weaker" than the many competing networks in my urban setting.

In adverse wireless environments (many competing networks on the same channel), 802.11b may slow down enough to be of marginal bandwidth for FLAC.

Try the troubleshooting outlined above, particularly the Network Test plugin.

Upgrading to 802.11g will not only help bandwidth, it'll increase security as an old 802.11b router isn't likely to have WPA.

I'm still scratching my head how playback speed would be affected though. It should play what's in the buffer at proper speed then drop out if the buffer is empty.

StadiumBlitzer
2006-04-22, 09:25
Unfortunately troubleshooting from this point is harder. We have to look for something that's causing SlimServer to bog down. Look at CPU usage, memory usage (shouldn't be a problem with 1 GB but you never know), etc. You indicate you're running the latest 6.2.2 - hopefully it's a very recent one (within the past two weeks) that includes SB firmware 37 as it's fixed a lot of problems. Also 6.2.2 has all the latest bugfixes.

Mark, sorry for the delayed response... I've been away most of the last week. I had a chance to install the 4/19 build and that seems to have improved things quite a bit. We were able to search/listen for over an hour without breakups. However, the slim.exe still goes berserk once in a while. Usually, it eats up ~55 MB of memory, but I've noticed when the breakups occur it skyrockets to 256MB. Also, it takes a heavy hit on CPU usage when it starts - but I assume that is caused by it reading my music folders (50GB on an external drive) at start up.

So, I think with your help I've narrowed it down to a performance rather than network issue, but I'm not sure how to monitor what makes slim.exe lose it. Speak of the devil... it just happened again. slim.exe has 99% CPU usage. I suppose I will try the latest build, but any ideas on what else I can try?

Mark Lanctot
2006-04-22, 10:10
So, I think with your help I've narrowed it down to a performance rather than network issue, but I'm not sure how to monitor what makes slim.exe lose it. Speak of the devil... it just happened again. slim.exe has 99% CPU usage. I suppose I will try the latest build, but any ideas on what else I can try?

Does it just do it on its own or are you doing something in SlimServer when this happens?

Things that may trigger intense CPU usage:

- browse music folder
- browse artwork
- rescan

There are some tweaks you can do in Server Settings - Performance but since I've never played with them I'm not sure what to change. Another thing to check is you don't have any playlists that point to missing files or recursive shortcuts or playlists (i.e. that refer to themselves).

BTW the rescan on startup was changed just recently and is intentional. Not everyone wants this behavior, myself included:

http://forums.slimdevices.com/showthread.php?p=103837