I’ve been having the same problems. For some reason I cannot get the system to work on my large 40-inch HDTV. I’m trying it right now on my small 22 inch HDTV. I know it works because the system turns on, and because I remember playing it on my small HDTV a year ago.
I am missing the N64 hookups however, and am using the RF Cable Adapter (the gray box with the coaxial sticking out on one end and a plug that goes into the system on the other) that used to work on the NES back in the day.
As soon as I get it hooked up we are going to jump into some retro action! Expect some retro videos (WatchMePlayGames Let’s Play) coming soon! :)