Can you post the serial number and if you can open the unit can you see if the internal fuses are blow. A photo filling the frame of the inside of the PS-100 would be useful too whilst you have it open (unplug any power cabling before opening the unit, and give it a few minutes to drain the filter caps before opening).
You could go through the NO SOUND checklist also are you using the top speaker out jack? Anything broken in your FX path? It’s a series loop so can cause this issue.