Hello everyone, Recently I bought a used 2-Channel H head after reading great things about them. The amp is in excellent condition and the owner still had the original packaging and stated he had never gigged with the amp. He also had recently done a complete retube on the amp, so I don't think the problem is related to tubes. One thing that's offputting is that the amp has a very noticeable hiss/hum on both channels, even with no guitar plugged in. The noise is present even with the master volumes turned all the way down, and it seems to relate to the levels of the FX send and FX return knobs on the rear of the amp. Even with them set low, the noise is what I would consider excessive. I did some searching and saw that the user henryjurstin13 had recorded two quick videos of the noise and they are definitely a good representation of what I am hearing: http://s76.photobucket.com/user/hen...B-47D1-A9BD-F3C964582F59_zpskuchr919.mp4.html http://s76.photobucket.com/user/hen...5-429F-B950-025C91418FCB_zps3ugoptas.mp4.html Another strange thing that I think may be related is that I don't seem to be able to get a usable signal from the FX send. I enjoy recording preamp signals into my audio interface by utilizing FX send or line out jacks and then utilizing cab simulation in my DAW, but the only way I can get ANY signal at all to my audio interface is to crank the FX send level knob all the way up and crank the audio interface's preamp gain all the way up (+45 dB), and then the signal is still extremely faint and the signal to noise ratio is atrocious. Does anyone have any ideas about what the issue could be? I've e-mailed PRS support but haven't heard back yet. If the fix is simple and inexpensive, I'd love to take it to a local tech, but am not opposed to sending it to PRS (although it would be nice to not have to pay for shipping charges both ways).