Non-optimal default settings for codec and chunk_ms?

[Tucker Kern]

The default codec=flac and chunk_ms=20 seem to be a non-optimal configuration. The comments in the configuration even indicates FLAC needs a larger chunk size.

snapcast/server/etc/snapserver.conf

Lines 144 to 150 in 8d282c5

 # Start Snapserver with "--stream:codec=<codec>:?" to get codec specific options 
 #codec = flac 
  
 # Default source stream read chunk size [ms].  
 # The server will continously read this number of milliseconds from the source into buffer and pass this buffer to the encoder. 
 # The encoded buffer is sent to the clients. Some codecs have a higher latency and will need more data, e.g. Flac will need ~26ms chunks 
 #chunk_ms = 20 

Some codecs have a higher latency and will need more data, e.g. Flac will need ~26ms chunks

In my testing, the default configuration causes occasional audible glitches with the following printed on the client

Feb 03 15:19:31 StereoBerry snapclient[30155]: pBuffer->full() && (abs(median_) > 2): 2282
Feb 03 15:19:38 StereoBerry snapclient[30155]: pBuffer->full() && (abs(median_) > 2): 2099
Feb 03 15:19:43 StereoBerry snapclient[30155]: pBuffer->full() && (abs(median_) > 2): 2701
Feb 03 15:19:54 StereoBerry snapclient[30155]: pBuffer->full() && (abs(median_) > 2): 2270
Feb 03 15:19:59 StereoBerry snapclient[30155]: pBuffer->full() && (abs(median_) > 2): 2569

Bumping chunk size of 40 seems to help.

[Tucker Kern]

These dropouts were likely due to my ALSA configuration and not snapcast.

[David Ventura]

How did you change your alsa config?

[Tucker Kern]

In my case I had an ALSA config that duplicated the stream, fed one into a dmix device and the other into a virtual loopback device. I simplified it into a single dmix device and the issues went away.

[STPKITT]

Please re-open this issue, maybe with edited intro post to make clear from the beginning, that your problem had another cause. This issue is still valid indeed, since it's still an error that the default setting for flac is chunk_ms=20 while the explaining text in the config files says FLAC needs at least 26 ms.