Can't hear microphone through speakers but level indicator show it is active

Running Linux Mint 20

With a microphone or guitar plugged into my audio input I hear nothing from the speakers.

The input level indicator in the sound settings is responsive but I get nothing in the speakers.

I'm assuming this is a default setting somewhere to prevent feedback but that's just a guess. Either way I can't find any settings to make it work.

Any advice or suggestions is welcome.

Thanks to all.
Cheers,