There was a kid at the track a couple weeks ago that was having a bad glitching problem...it would work OK up close, but walk away and it would freak out and stop doing anything. It was a Spektrum/M11(pretty new)/GTB deal...we swapped out everything one at a time and nothing fixed it.
Bound my transmitter (beat-to-crap M8/Spektrum) to his car and it worked fine. It had a bad range problem for some reason...battery charged up...it was like new, but it didn't work right at all.
I'm not saying that's it, but it might be...
But hey...if you decide to dump it, toss it my way.