I had the exact same issue. Playin on my roommates 47" LG tv downstairs I get that delay between controller and tv. It's not network related at all because I get the same delay playing the single player campaign. I play upstairs on my old 32" tv and don't have the issue at all.
It's something with the tv or xbox settings I think but I could never figure it out. I just play in my room now lol
Edit: It also didn't matter if I used a wireless or wired controller.
This post was edited on 3/1 at 12:26 pm