Microphone Distorted After Suspend/Resume

[Guest]

Hi All,

I have (fortunately) a very consistent problem. When I initially start my computer and check my microphone using arecord+aplay, everything responds correctly (and even appropriately picks up the incessant whirring of my fans ). However, if I suspend the system to RAM and then resume, then the input consists of a loud and obnoxious buzzing regardless of whether the microphone is even plugged in. Moreover, while it does "respond" to my voice, it merely adds a touch of bit-crushed tonal variation to it. I can provide an example upon request, but the summary here is that it goes from perfectly clear to perfectly painful.

My sound card is an HT Omega Claro, no plus, not a Claro II, etc. so it uses a CMI8788 chip which as I understand it is supported via snd-oxygen. Any solutions to this would be appreciated, including some way to just completely reset the card on resume since it seems like some bits get stuck in a buffer or something bizarre that I don't understand.

Thanks in advance.

[SteveRiley]

Here's a guess... try unloading and reloading the kernel module (driver) for the card after you resume.

sudo modprobe -r snd-oxygen

sudo modprobe snd-oxygen

Does it help?

[Guest]

I feel pretty dumb. Although I had tried force-reloading alsa, I had ignored the bit where snd_oxygen wasn't being unloaded. Following your directions forced me to confront that fact. After going through all of the nonsense in order to kill all the processes using the module I was able to reload the module which fixed my problem. Many thanks for that.

The only other thing I could ask for is a way to save the state of the various volume controls and restore them after reloading the module, but at this point I'm content to leave well enough alone and be happy with what I have.

[SteveRiley]

No need to feel dumb -- one the things we must come to expect as Linux users is that we'll need to develop a closer relationship to how the software and the hardware interact. It's a learning experience.

I'm surprised that your volumes aren't staying put. Normally both ALSA takes care of this for you. But it could be that your sound hardware is so uncommon that ALSA simply has no way of keeping track of that information. I dunno, really; Linux audio can be...challenging, at times