I just got the Wii U Mario Kart 8 bundle the other day, and everything was working fine the first couple days. On the third day however, I started having this issue. The screen flickers and glitches with random colors, and makes a loud crackling sound. It only seems to do this when I am actually using stuff for the Wii U (such as the Wii U menu, Mario Kart 8, etc.) As soon as I load up some virtual console games (such as Earthbound or Super Castlevania IV), everything works fine until I exit the game to the Wii U menu, and the problems start again.
I have already tried switching to 1080i instead of 1080p, as well as all the other choices (720, 480) and this didn't do anything. I also was going to try a different HDMI cable, but when I unplugged the HDMI cable, I noticed the Gamepad had not stopped the flickering/annoying noise. Short of trying a different tv, is there anything else I can do? Thanks!