A new video describing a problem that I've been struggling with for a lot of time:
Regarding the problem of amp auto-shutdown, I figured it out. It's because I have the blue trace on the amp input and when I connect another probe to measure the input current I'm making a ground loop. The amp is a good device with a good protection.
I would be glad to read your opinions on how to solve that noise. The probes are compensated well, the scope is calibrated by the book, so I can only imagine it's because of the mains connection.
"It's just the knowledge of the coils and how they interact with each other" (Steven Mark)