by garfy » Wed Mar 17, 2021 3:09 pm
Hi John and welcome to the forum.
Well, the most obvious thing from that description is you should check that the Direct Monitor button on the front of the UM-2 is not pressed in. That should then let you hear audio from your PC.
If that is already correct, are you seeing the input and output meters moving on the AT5 interface when you play your guitar?
System Specs: 2012 Mac Mini 2.6 i7 & 2015 MBP 2.2 i7, 16GB RAM
macOS10.15.7 Logic 10.6.1 Reason 11
Various IK, NI, Waves, Softube, Eventide, XLN software
Focusrite 18i20 x 2, Novation ReMote 25SL