I'm not versed in the wiring diagram of OL's. But am fairly versed in stereos. I assume it's a standard head unit, connected to one (or more) amps, couple of subs and mid and highs?
Depending on how it's wired: If the whole system is shut down, or if there is just no sound because your amps are getting no power. Locate the power cord, connected to the battery and follow it back to the stereo. Somewhere along the line, there will be a main fuse. That is probably your culprit. Now, the peeps at OL may have told you not to bother looking for it because it's in the gunwalls or its stashed behind the head unit to keep everything nice and neat in the engine compartment.
On a related note: when you're all blotto on the lake and the chicks are dancing, taking off their clothes off and everyone is partying like rock stars, I know it's not the first thing on your mind to keep an ear open for that distortion in the stereo that happens when the amps are getting hot or when you're just pushing the system too hard, but to avoid fuse blow out in the future, this is something that needs to be done!