Logitech Q9000 default mic gain too high, causes distortion

[Russell Keating]

The file /var/lib/alsa/asound.state has the following part for the settings for the Logitech Q9000 camera.

control.3 { iface MIXER name 'Mic Capture Volume' value 0 comment { access 'read write' type INTEGER count 1 range '0 - 3072' dbmin 1800 dbmax 3000 dbvalue.0 1800 } }

The dbmin value of 1800 (18db) is too high and causes the mic signal to be distorted. The value should probably be 0 and the default value (dbvalue.0 1800) should also probably be set to 0 (0db) and not 1800 (18 db.)

With the dbmin of 1800, it is impossible to set this any lower than 18db in alsamixer.

In my system, this value comes from /proc/asound/card1/usbmixer and is linked to /proc/asound/Q9000/usbmixer.

I've tested this out by editing /var/lib/alsa/asound.state to set dbmin and dbvalue.0 to 0 and the sound on the microphone stops being distorted.

Description: Ubuntu 21.04
Release: 21.04

I have not idea what the package is, but I listed the files so hopefully that is good enough.

What I expect to happen:
To have the default value for the mic gain to not default so high as to cause distortion and the the value to be able to be set to 0db (or less even?) in alsamixer.

What mappened instead?
The mic distorts because the lowest available gain is 18db. You can't set this below 18db in alsa mixer. This happens in any program that uses the mic input.