Sounds to me like you've got a power wire that is shorting to the frame somewhere. What exactly have you done, electrically? I had a problem with mine also, and found out when the guy ran my power wire back to the trunk for my amp, when he reinstalled the bolt that holds the seatbelt bracket, the wire was too close to the bolt and the threads cut the insulation of the wire causing it too short. Luckily it didn't catch fire !!!
Oh MY GOD I figured out what it was... Ok here's the story: I bought a power inverter, and I hooked it up to my laptop. Then I hooked up my laptop to the power inverter and plugged my laptop into the amp and I heard this WEIRD *** SOUND to the speakers and burning smell.. That was the first time it blew up... then after about 2 hours of unplugging all my electrical stuff I decided to take off my car stereo (stock HU) and as soon as I took it off it stopped blowing up the fuse..
QUESTION: Can I get a new HU under warranty? I really don't need it anymore, but I want a working hU in case I want to sell the car/trade in etc etc, besides it's under warranty
What would you guys recommend me? unplug everything and return back to stock? they are never going to know it's the stereo unless I tell them what I did.. they are going to take my car apart thinking it's a ground problem and it's the stereo that's blowing up the fuse...