So I'm a drummer but I have an amp related question...

My band's guitarist has been having a terrible time lately trying to get his equipment to function. First, he was using a 200w Randall RG200 Head and a 4x12 Randall cabinet - which was awesome - but the Randall was experiencing some volume loss and a bad signal so we put it aside and decided to look for a new used amp. I assumed he would try to get a tube amp, but he ended up buying a Marshall MG100DFX in so-so condition instead. After he got it, he plugged the Marshall head into the Randall cab and it immediately fried itself (with a small smoke puff). Now there is no power whatsoever.

I really know very little about this kind of stuff, but my FIRST impression was that he got screwed on ebay buying a bad amp. Now, I'm thinking it was the Randall cabinet that fried the Marshall head?

Does anyone have any ideas what happened?

Hi.

I own a 200w Randall RH200SC which seems to be exhibiting a few problems. The volume cuts out every time I play it and this will *generally* get better after 60-90 minutes of high volume playing. If playing at lower volumes the amp is virtually unusable. It's a solid state and I thought if I dismantled the case and took it apart I could see a bad solder joint or loose connection, however everything seems to be tight and clean. I would prefer to get the problem fixed myself and not send it off to pay $200 bucks for something I could fix myself. So does anyone know what I'm talking about and/or have any advice? Thanks!!!