MA2275 Issue need some advice

Lapierre, checked the cables and the interconnects, even removed them and connected with bare wire still having the problem. You said to check the fuse before, wouldn't the fuse either work or not work? Their is only one fuse so wouldn't that effect both channels? It's a slo-blo type fuse.

Someone else may want to check this to make sure. When I read a schematic like this (lot of parts) from a pdf reader, I get eye fatigue.

Anyway the way I can see is the V4 and V5 are for the phono. They share the left and right half in each individual tube.

The V6 and V7 (gain tubes) also share a left and right in each individual tube.

So assuming the V4 and V5 was physically swapped left to right side (of amp), the V4 and V5 would have should have replaced the gain tubes V6 and V7. I'm thinking the phono (V4+V5) and gain (V6+V7) shouldn't have a bad section on the same side (half) of two tubes. At least it doesn't seem likely, but strange things can happen. A lot of other parts in there. Possibly a solid state part, or other. You could call MAC to make sure also.

The center tubes (V5 to V7) aren't mirrored on top of the chassis, meaning the two on the left isn't for the one channel, and the two on the right side are not for the right channel only.

All of the other tubes (not center four) are for the side they are on I believe.

Link for schematic for anyone else. [http://www.berners.ch/McIntosh/Downloads/MA2275_ser.pdf]

I hope your using other inputs than phono also. And, if it did the same with other inputs, the above would have worked. Otherwise it could be a bad gain, or phono tube if you just used phono in.

The center tubes (V5 to V7) aren't mirrored on top of the chassis, meaning the two on the left

Correction: Should have wrote (V4 to V7)...

Hifihvn - wow thank you so much for looking over the schematic and comments!!! I'm only using the CD input, not phono at this time. I did swap CD and CD2 but same result.