What is the problem with my Marshall JCM-900?
Over the past few months, my 50 watt JCM-900 (tube amp) has started fine. After a few minutes of playing, it fades out then fades back in. This continues for the duration of my playing. I even tried to run the head directly to a recorder, and it did the same thing. I have changed out the tubes, and the problem still persists.
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