Adding / removing USB devices usually sets it off faster than anything else. But it's been known to just randomly do it.
Updated sound card drivers didn't fix it.
Original sound card drivers didn't fix it.
Reinstalling the OS from the recovery partition didn't fix it ( and it didn't install ½ of the pre-installed ASUS utilities that were on there before I did it )
I've thought about skipping the ASUS stuff altogether and just putting Windows 7 on it from a clean ISO.
ASUS thinks I am having a hardware issue and wants me to send it it for repair.
I am a little scared to do that since the last time I sent my laptop into ASUS for repair the damn thing got stolen on the return trip. It's how I ended up with the G73 I have now.
The good news is that I do have LoJack for Laptops enabled on it

Which works very well, I was in Wichita this weekend:
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