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matek994
2007-11-29, 06:27
Hi,

trying to find out why FLAC songs don't play smoothly on my SlimServer+SB. Looked into the preferences file and found the following setting:

maxbitrate: 320

Can I increase this?

Mats

Mark Lanctot
2007-11-29, 06:36
What do you mean by "don't play smoothly", are you getting dropouts?

In which case, increasing the bitrate will make it worse, you don't have enough wireless bandwidth. See http://wiki.slimdevices.com/index.cgi?NetworkProblemsSecondGuide

Not only that - I'm not sure where you're seeing that setting or what it's doing. It seems to be a bitrate limiting setting - this will transcode the FLAC to MP3 at the given bitrate. In Player Settings - Audio, you have to activate bitrate limiting, have LAME installed and have FLAC -> MP3 checked in Server Settings - File Types in order for this to work. If it's not activated, activate it, and if it still stutters, turn the bitrate down. You can't turn it up from 320, that's the maximum a standard MP3 encoder allows.

But all this is turning lossless files lossy, so it's best to try to address bandwidth concerns first.

matek994
2007-11-29, 06:57
Hi,

thanks for your reply.

The problem I have is that when I select a song which is in FLAC format (MP3's are not affected) it starts to play, but then there are intermittent dropouts during the first half minute or so. After a while the song plays alright. Any subsequent songs played w/o user interaction play alright.

I have run the SlimServer's network performance test with perfect results up to 4000kpbs, so I doubt this has anything to do with the capacity of the network link.

I also run the SlimServer's server performance monitor, which reported that the player buffer is never filled to any higher degree.

Apparently there's a bottleneck somewhere, the player not being fed with music at a rate that saturates the SB while playing, at least immediately after being instructed to play new songs.

Any idea?

Mats

PS. I am running slimserver on an NSLU2.

Mark Lanctot
2007-11-29, 07:03
PS. I am running slimserver on an NSLU2.

Oh oh. Probably the lowest-power CPU that's still capable of running SlimServer.

What version of SS?

Can you run Server & Network Health as outlined in the wiki? (Not this is NOT the network test you posted.) Post the server health stats.

Robin Bowes
2007-11-29, 07:11
matek994 wrote:
> Hi,
>
> thanks for your reply.
>
> The problem I have is that when I select a song which is in FLAC format
> (MP3's are not affected) it starts to play, but then there are
> intermittent dropouts during the first half minute or so. After a while
> the song plays alright. Any subsequent songs played w/o user interaction
> play alright.
>
> I have run the SlimServer's network performance test with perfect
> results up to 4000kpbs, so I doubt this has anything to do with the
> capacity of the network link.
>
> I also run the SlimServer's server performance monitor, which reported
> that the player buffer is never filled to any higher degree.
>
> Apparently there's a bottleneck somewhere, the player not being fed
> with music at a rate that saturates the SB while playing, at least
> immediately after being instructed to play new songs.
>
> Any idea?
>
> Mats
>
> PS. I am running slimserver on an NSLU2.

I'm almost certain this is a CPU limitation of the NSLU2.

When bandwidth limiting is enabled, slimserver transcodes the flac files
to mp3 (using lame) to reduce the network bandwidth used by file
streaming. The NSLU2 won't have enough CPU power to do this.

mp3 files are not affected because they are streamed direct to your SB.

The fix? Turn off bandwidth limiting so flac files are streamed natively
to the SB.

R.

matek994
2007-11-29, 09:33
My SlimServer version is: 6.5.2 - 12047 - Debian - EN - iso8859-1

Regarding the "maxbitrate" setting, I guess it is perhaps not relevant in this case. The Server Settings reveal that FLAC files are streamed as FLAC. The Player Settings show Bitrate Limiting = No Limit. Sorry for misleading you.

I uploaded the performance log to a temporary web area instead of pasting it here as it became quite large. If you find some hot areas in there, I'll include those in a following post.
http://members.chello.at/matsoek/temp/log.txt

FYI, a few hours ago I posted another question in another area of this forum, http://forums.slimdevices.com/showthread.php?t=40671. It describes my setup a bit more in detail if needed.

chesebert
2007-12-01, 17:24
I have the same problem playing high bit rate FLAC 24bit/96Khz file I bought. The sound would have couple dropouts in the 1st min and everything plays fine; granted if I start the song over again I don't get the same problem. Annoying.

Transporter - Firmware 33
SqueezeCenter 7.01a

bpa
2007-12-01, 18:03
matek994,

How did you create the Flac files - there was another post about dropouts on native Flac playback and it seems that the encoder may be the problem.

chesebert
2007-12-01, 18:56
matek994,

How did you create the Flac files - there was another post about dropouts on native Flac playback and it seems that the encoder may be the problem.

The flac are bought from linnrecords @ 24bit/96Khz master quality;

If I let the flac file play for say 20 sec and start the file over, I don't get the sound drop out.

If I put all the flac in a playlist and just let one song play after another, no drop out.

The network performance tests to 3000kps @99% (I am thinking my problem is network related as the files are 2900kps)

My squeezecenter version is SqueezeCenter Version: 7.0 - 14627

bpa
2007-12-02, 02:26
chesebert,

This could be a Transporter buffering problem which is exacerbated by the additional small delays inherent when using wifi.

The fact that you can get continuous subsequent audio - means that although your wifi may be marginal - it is OK.

When a track is being played - the Transporter buffer is initially filled up and then when full "play" is initiated. It looks like the Transporter waits just a little bit too long (when using marginal wifi) before asking for the first top up of the buffer. This might because you are using Flac 24bit/96KHz files which require high datarates.

I think you should log this as a bug.

matek994
2007-12-02, 09:34
I ripped/encoded my songs into Flac format using Exact Audio Copy v0.99, default configuration. It seems to call an external encoder called flac.exe v1.2.0 by J. Coalson.

Mark Lanctot
2007-12-02, 16:04
I have the same problem playing high bit rate FLAC 24bit/96Khz file I bought. The sound would have couple dropouts in the 1st min and everything plays fine; granted if I start the song over again I don't get the same problem. Annoying.

Transporter - Firmware 33
SqueezeCenter 7.01a

Sounds like this bug:

http://bugs.slimdevices.com/show_bug.cgi?id=4463

Either don't use ReplayGain or the spectrum analyzer screensaver.

schiegl
2007-12-02, 22:23
concerning FLAC 24bit/96Khz files: I have a few ones which show these problems even with replay gain disabled and no screensaver at all.

the only workaround i've found so far is transcoding on the server side to flac-compress level 0 to relieve the transporter CPU.

convert.conf:



#flc flc * *
# -
flc flc * *
[flac] -dcs --skip=$START$ --until=$END$ -- $FILE$ | [flac] -cs --lax --totally-silent --compression-level-0 -


unfortunately this disables fast forward/reward (which i don't care) but also seek support using the progress bar on the webinterface.

regards,
Markus

Mark Lanctot
2007-12-02, 22:24
concerning FLAC 24bit/96Khz files: I have a few ones which show these problems even with replay gain disabled and no screensaver at all.

the only workaround i've found so far is transcoding on the server side to flac-compress level 0 to relieve the transporter CPU.

convert.conf:



#flc flc * *
# -
flc flc * *
[flac] -dcs --skip=$START$ --until=$END$ -- $FILE$ | [flac] -cs --lax --totally-silent --compression-level-0 -


unfortunately this disables fast forward/reward (which i don't care) but also seek support using the progress bar on the webinterface.

regards,
Markus

Please add this info to the bug report.

schiegl
2007-12-03, 14:23
Please add this info to the bug report.

Hi Mark,

done. added a little summary to this case...

kind regards,
Markus