Firstly, thank you in advance to anybody who responds. If this is in the wrong area, mods, I apologize - please of course move it to a proper location.
I recently borrowed a Mackie FR800 power amp from a friend and used it for a few weeks with no issues. Upon returning it, of course one of the channels would not work for him (Ch1).
Opening the case, two of the fuses looked bad. Replaced them with 10A fuses (same as stock), and powered on. The ceiling lights in my garage went dim for a moment upon powering the amp on, and one fuse fried within less than a second. Channel 1 of course still does not work. Channel 2 operates with no issue (before and after the fuse swap - appears to be utilizing the other 2 fuses and is unaffected by the issue).
Any ideas what this may indicate? Perhaps something is grounding out or surging somewhere? I'm attaching a few pictures for reference. The fuses are in the back left corner. I'm just not sure where to start.
Pics are on my WebShots at: http://community.webshots.com/album/582912042lClSps