Why is laptop sound decreasing and then Muting while broadcasting and streaming music

I have a Dell inspirion that i use to broadcast and stream music , which is using a cirrus encoder by securenetsytems for my IOS and Android apps , my music is being stream from my OTSAV radiocaster program , I also use a Yamaha 4 channel sound mixer for my guest to be heard on stream while using microphones connected thru an USB  external sound card.

Problem: while doing interviews once i switch the encoder from WASPI to Microphone 2 channel, My Laptop plays and then the audio decreases and then mute itself, so the sound can no longer be heard on apps, but audio can still be heard thru sound board and on the apps

Question: Any Ideal why this is happening, I have updated from Windows 10 which was have a audio update problem , to Windows 11, that did not solve the audio issue,  Please advise if this is a known Audio issue with Windows operating system.