So I have been having this same issue for months now. My solution originally was to just unplug the speakers from the line out, and just manually switch between the two, but upon having some sound issues’ this weekend where my sound was going in and out, I decided to try some troubleshooting to figure out if I could fix the original issue of the line out on the receiver. I went through everything I could think of, and the problem ended up being the USB port that I was plugged into. I cleaned my desk months back, and must of plugged the receiver into a USB 2.0 slot on accident, so if you haven’t already try changing the USB slot to make sure you are plugged into a 3.0. TLDR - try changing USB slots on your PC