My Yamaha EMX512 is on the fritz

It worked fine yesterday. Today I turned it on and all I'm getting is loud hiss:sqerr:. So where do y'all send your equipment for repairs? Any ideas what might be wrong?

Now I understand why so many of you talk about back up equipment all the time...

I'm one of those people who doesn't bother with repairs and just replaces the bad equipment. On that note, did you check first to make sure it wasn't a bad speaker cable or perhaps something loose? Sometimes I don't think about this until somebody else asks.

I take my equipment to a local shop that repairs and cleans everything. Works well for me.

O M Gosh, I didn't expect this. I feel like Charlie Brown. This really sucks. Fortunately I don't have any gigs right now or I would be scrambling for a replacement. I don't like scrambling.

Ok, I messed with it some more and turned it on and off, switched cables around etc.
In regular stereo mode both channels work fine. In bridged mode if that's what it is, where you can have mains and monitors, there id a switch to set this, one of the channels is all hiss. I need to mess with it some more to try to figure this all out. . .

If it works in stereo then what is the problem?

The switch sends left and right mains to one channel output and the monitor section to the other output if you don't have anything going into the monitor section of the board then there shouldn't be any sound, but if you have a channel with no music or mic but some processing going on and the monitor pot turn up or just the monitor pot turned way up you will get floor noise.

Turn all monitor pots one each channel off turn the main monitor fader (or pot) up, then play music through a channel and slowly turn up the monitor pot on that channel, if you have sound then there is not a problem!