it actually doesnt happen as often as you think. sounds splatty, with very little volume. i will aslo eventually damage the preamp tubes/power tubes. depends on which coupling caps they are.
Thanks for the info, I don't think I've got the problem then. I changed out the big filter caps, so I was worried that the others would need doing as the tone controls don't seem to do a lot so I suppose that must be normal for MV type Marshalls.
I've only experienced that once, and the amp just died and stopped working.
When they replaced them, they used better ones, and told me that the stock ones were feeble.