I hooked up my notebook to the stereo and tried to play some songs. I wanted to check how high I could crank the speakers and it started to hiss very high for about 3 seconds and now, when I change the balance from one speaker to another, there are no "highs" from one speaker. Could it be that I just blew a fuse or something? Those are some old-school Revox speakers, about 80cm high and really big. Any chance that I could fix that?