ALSA sound suspend/resume

[Sean McNeil]

I had an issue with ALSA sound not coming back on resume. This looks 
like it might have been an application error where I was setting the 
start threshold via snd_pcm_sw_params_set_start_threshold() to the 
buffersize. Lowering by a periodsize seems like it resolved the problem.

Now I would like to fix the popping noise produced when suspend or 
resume occurs. I think it is because the amp is turned on with the 
volume up. Is there some ramping that needs to be done when turning 
on/off the amp?