I have a Roland KC100 keyboard amp that died on me. First,
I started noticing an annoying low level ring from the
speaker when my keyboard was hooked up. I thought at first
it was a ground loop, but I couldn't get it to go away.
Then, the amp started cutting out for brief stretches of
2 or 3 seconds. The sound would die out and the power light
would fade off. But it would usually come back on by itself.
When it didn't come back, I could sometimes get it back by
jostling the unit. Finally, it died altogether. When I power
on, I hear a faint "power on" sound from the speakers, but
I get no sound from my inputs anymore.

A guy in a local music store told me, "Sounds like you blew
a capacitor in your amp."

Does anyone here have a good idea of what might have happened?

I have no experience with such things, but I'm hoping I
might be able to do the repair myself, to save the $100 or
so a shop would charge me. Does anyone have any comment on
how advisable that would be or how I'd go about figuring out
how to fix it?