Topic: New 3DS XL Blank Screen at Startup

Ok, this is the second time this has happened to me. I got the new 3ds right around the time it came out. It worked really well for the first few weeks, but then I opened it up to play Pokemon, and the screen wouldn't come on. I tried every thing, except ripping it open and trying methods on the Internet, which would have voided my warranty. I sent it in and when I got it back it worked fine. I've had the same 3ds since and 2 days ago I was playing Mariokart DS and when I quit to the home menu, it went black. This time it is different though, because I can hear the home menu music playing. I tried blindly opening Mariokart DS, and it worked. The screen turns on displaying the Mariokart logo and the game works fine, except the screen flashes different colors randomly while playing the game. I tried playing other games, but they don't launch so the problem is probably correlated with Mariokart, but I don't know anything for sure. Any ideas would be greatly appreciated.