Soundcard muted

[Liedzki]

Hello,

I wanted to play some music, when the photo booth is in use. I wanted to use an audio player, like audacious, to play music.
I added a iquaudio digiamp+ on my raspberry pi 4, but if I start pibooth, the soundcard is muted. If pibooth is closed the, the soundcard keeps muted. It is unmuted if I restart raspian.

I'm not familiar with programming, but with a little guidance I'm confident I can implement a solution.

Thank you in advance!