I have basically the same problem. I found an old H3000SE in the back of a studio and I have been trying to get it to work. I managed to get the OS to reset after this the unit let a signal through when it was not bypassed, but it was lower than the bypassed signal.
Did you find a solution? Is there any place where a solution might be found. I live in Taiwan and there are no repair serviced listed for this region on your website.