So im working on a setup at work, but i ran into a wierd problem where when using the internal Intel_HDA system where if i lets call it "turn the wrong"(out of like a million knobs and buttons), the alsa system basically kills the input sound system, and it becomes garbled and basically sounds like everything is recorded below a water surface, and im unable to revert back to an earlier state.
I really have a grief with the intel driver for alsa since its just rediculesly over-engineered, i mean compared to a USB, which has like 3 in/outputs, device it has like 10 times the knobs and buttons you can turn in alsa mixer/amixer, and turn the wrong one and it destroys everything.
Any ideas might be causing this?, my guessing some kind of wires gets crossed at the analog to digital level, but sofar i have no fix for it, and it's pissing me off honestly since it is so simple that i basically just want to turn up the input sound, thats it, not destroy the whole OS setup.
Why are you using alsa, and what do you need to use it directly for over for example pulseaudio?
The setup were using uses some external home made hardware which just killed PA, my original plan was PA, and it worked like a charmed right up until the home made HW was connected.
PA was so easy to setup, think i used like 5 lines of CLI to basically setup everything, but the external HW just killed it, so had to change strategy e.g. alsa, since i really didnt wanna touch the Elephant in the room called oss.
It should be noted, Alsa isn't bad at all, few setup files and what not and you're balling, what kills me is the intel hard/software, those retards really did a bad job what constructing the driver, i mean it is redicules the amount of buttons even alsamixer has, it is proberly ~20+ dials for the PCH sound device alone, then there is the built in HDMI sound on top of that....
If i set up everything as "suppose to be" it works orgasmically(It really does work that well), but if i turn a wrong dial it destroyes everything, and im unable to recover to a earlier state.
Sad thing is i need a way to do the setup while running live, and if some "operator" decides to twist the wrong button, it means we need to send a repair guy(which here is not cheap), which is just a dumb cost for for something which is suppose to be easy peasy to set, except intel made it hard by over engineering something "simpel".
Is there a specific wrong control in alsamixer? unclear whether this is digital or analog, but switching to the wrong audio output type or changing sample rates on either can create effects you stated.
Try to get any non-relevant audio controls muted and on zero.
suggest you store known good alsa settings in home folder, in addition to usual system file /etc/asound.statealsactl store -f ~/asound.state
then alsa can be reset with alsactl restore -f ~/asound.state
could use this command in a bash script linked from a desktop/panel icon, then users can click this reset button and shouldn't need to go to audio mixer
But once alsa is set correctly it shouldn't need to be adjusted
If changing alsa controls is really problematic, use amixer command in terminal to make adjustments - amixer manpage
Intel hda driver as it is in the linux kernel, is the driver for pretty much all regular consumer class class compliant audio hardware, it is not intel specific, it is a dumping ground for the "rest category". That's why there are too many controls for most actual audio interfaces that use it.
Now normally, on decent hardware, it's not really a problem, but there are some cases in which it can become a problem, the main one being that it's possible to create a resonant feedback loop, and if the hardware isn't secured against that, you can actually kill the hardware with that. Not all PC audio interfaces are made to do input monitoring, but linux provides that functionality in general.