choppy sound on alsa after 30 min

Question

I am writing to alsa in 10ms period to play music, it works great at beginning, however, it has some choppy sounds after 30min playing, and the choppy sounds only lasts for a few mins.

Any ideas why?

Environment is: Arm cortex-A8 audio codec TLV320AIC3106 linux kernel version: 3.2.0 os: ubuntu 12.04.2 LTS

Answer 1

Ok, I found the problem.

On PC, we don't need to call snd_pcm_sw_params_set_avail_min, it works great. However, on our arm machine, we have to set it, otherwise, the status of the buffer is unpredictable, which caused choppy sound and background noise. And when you check the status of the playback device, u won't see the underruns, everything is works great except the avail and avail_max values.

Hope this will help someone else. :)