[Linphone-developers] mediastreamer2 file play crackling sound due to underruns

[Matteo Fortini]

We are experiencing crackling sound when playing wav files through 
mediastreamer.

We copied the tester/mediastreamer2_player_tester.c file and modified it 
so that it plays any filename passed as the first command line param.

The issue is audible when playing wav files both through pulseaudio and 
ALSA. We changed pulseaudio.c code so that it outputs every underrun it 
sees, and the crackles are at the same time we have an underrun.

It is not CPU related, since it happens both on a small ARM system and 
on an 8 core Intel i7.

It may be something connected with tickers, which sometimes are late, 
but latency seems not to be the issue: we printed pulseaudio latency and 
it is not worse when crackling than when not crackling.

Is there anything else we could check to narrow down the causes?

Thanks in advance