Mamba Monster 2 stops and starts...

[dadgummit]

I just built and converted a Hot Bodies D8T. I used a Castle Mamba Monster 2 with Neu 1515 2200kv combo. The truck runs great but after about one minute it started to do a strange thing. It will be going along just fine and the truck just loses power and stops. For the next about 5 seconds neither forward nor reverse does anything then the ESC beeps like I just turned it on and it will go again for another 10-20 seconds then it will stop again.

Both the fan on the ESC never stops spinning and the steering servo works during the 5-seconds just no forward nor reverse.

I tried 2 different batteries (both are turnigy 6600mah 60C 4S batteries that were fully charged. I tried 2 different receivers (both spektrum receivers that I have used on several other cars with no issues at all).

This is just in by southern california back yard (small) so there are no range issues. It will often stop within a couple of feet from me.

Does anyone have any idea what could be wrong?