Levinson JC-1 - CJ 10b = blown Yamaha M2?

Time to fire up the stereo.
Pink Floyd - "Wish you were here" seemed like a good test of my new CJ 10B. Hadn't tried anything quite like that yet.
Got into the intro, everything seemed good, the lights in the room dimmed for a split second, the Yamaha M2 went quiet for a second. The right channel of the power amp is now gone. I tried switching the leads from the CJ, still have a signal to the left but no right.
Being fairly adept with a screwdriver, with cover removed, I found not a fuse in sight. I had for the longest time noticed a bump, if you will, in the right channel a few minutes into listening each time the Yamaha M2 was fired-up. I suppose the bump has now bumped for the last time. I think you would agree the amp is not worthy of repair, but don't want to do the same thing with a new amp.
In using the CJ phono stage, I found a need to use my Levinson JC-1 cartridge preamp. Without it the Supex sd9000 needed a lot of volume attenuation. In that I was listening to an album at the time of the catastrophe, did the use of the JC-1 cause the right channel to let go some how?
I wonder did I foul-up by hooking the Mark Levinson JC-1 to the phono input of the 10b?
Without the cartridge preamp I found it necessary to turn the volume control well past 12:00, with the Levinson only to 9:00 or so. The preamp sounded great prior to this episode, I can't believe the CJ created the problem. I would certainly appreciate any comments.

I think that the Yamaha was at fault but you might want to have the CJ checked for passing DC. Did you ever switch input leads on amp to see if the thump moved or stayed the same? The JC1 is most probably NOT at fault and from you description you used it properly.
The bump was always on the right side, leads switched or not.