Audacity input level fixed 100%

[Frank Vanoni]

In Audacity, the input level slider (eg microphone) is fixed at 100%.

I read online that to adjust the input level you need to use
pavucontrol (Pulse Audio volume control). 

However, if I open Pavucontrol to adjust the level, Audacity no longer
recognizes the audio source (eg microphone) and indicates an "Error
opening device - Error Code 9985 - Device unavailable".

Does anyone have a solution?

Ubuntu 22.04.3 LTS + Audacity 3.3.3