ALSA sound system problem with Microphone

I had problem with ALSA (alsamixer) on my CentOS.

Inside /etc/asound.conf there is a hooks section.

The hooks section introduced another sound card and I was not able to use the microphone after that.

After deleting the @hooks section the problem was gone.

Here is what I understood from the problem:

• /proc/asound/ - this folder actually determines if alsa is present on the system or not.
• alsactl restore 0 - sound card 0 info will be restored
• alsactl store - this enables alsa to store permanent values
• arecord -vv -d 10 test.wav - creates a file after 10 seconds of recording with the visual equalizer
• aplay -vv test.wav - plays the file
• alsamixer - of course the most important to set the levels
• pulseaudio --kill - eliminates pulse audio
• pulseaudio --start - starts pulse audio
• pacmd list - closer look to pulse audio

The nice info about ALSA:

• http://www.seehuhn.de/pages/alsa
• https://wiki.archlinux.org/index.php/PulseAudio

BACKGROUND

ALSA is the kernel level sound mixer, it manages your sound card directly.

ALSA by itself can only handle one application at a time. This may be a problem, but there is dmix module, written to solve the problem of one application at a time.

PulseAudio is a software mixer, on top of the userland (like you’d run an app). When it runs, it uses Alsa’s channel - without dmix - and manages every kind of mixing, the devices, network devices, everything by itself.