SirPhantom

I just decided my WiiU was faulty and took it back to get it replaced. Good thing I still had the receipt. I forgot to return the Wii Wheel thing though, but they were nice enough to just take that out of my replacement bundle to compensate. Everything has been working fine so far now.

I was just unlucky enough to get a broken system fresh out of the box. lol

I worded my OP wrong about the tv turning off. It's just the console itself that suddenly shuts off. After that, the only way to turn the Wii U back on is to unplug the AC adaptor and plug it back in. And the Wii U isn't in any case, aside from an extremely large and open shelf with plenty of space.

Brand new disc. No scratches at all.

I am playing in 1080p. That causes problems?

This problem only seems to happen when I'm playing Mario Kart 8. Using the console itself has no problems and I tried another game to see if the problem continued (Super Smash Brothers Brawl) and it ran with no problems.