First off: Thanks so much for your help!
I am in the process of testing what you guys suggested. Of course today everything works fine, I`m very sure though, tomorrow when I`ll be teaching it`ll appear again;-))

I thought about the wires too, since they are the same age the old amp was (hmm, I moved in in 1990 - daaamn;-)) But so are the speakers...

But to exclude the Poti theory I will plug the headphones into the amps the next time it appears again. If the crackle ain`t on the headphones it can`t be the volume poti.

I`ll let you know my testing results.

Sandra


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