Strange glitchiness with sidewinder and MM with ccbec

[Sammus]

Howdy, here are my two setups I'm having problems with:

Jammin CRT.5: Mamba Max, Feigao 9L, 4s1p A123, ccBEC, 12/46 gearing (~33mph)

Rustler: Sidewinder, Ammo 36-56-3300, 3s1p A123, ccBEC, 12/40 gearing (~40mph)

Both of the cars are running Futaba R603FF 2.4Ghz receivers and I use a 3PM transmitter, on both the cars I have removed the +ve wire from the esc to rx lead.

Both the cars have acquired a strange glitchy behaviour since switching to A123 cells (both of them used to run 3s lipo). It seems like sometimes if I gas it, the throttle locks on for a second, and often causes the car to go somewhere I dont want it to :(

I've never had any glitching before, does that sound like radio interference glitching? I though 2.4Ghz was near immune to glitching?

At any rate, I removed the ccBEC from the rustler, which let me tidy up the wiring a little better, and in the extremely short (ie a few minutes) run I gave it doing circles in my garage (it's been raining heavily for a while now..) - where I've recently noticed the glitching during my test runs of both vehicles - I wasn't able to replicate the glitching again.

Redoing the wiring on the CRT.5 will required me to redo my chassis layout, so I thought id ask if the kind of glitch I described (momentary throttle lock on) sounds like radio interference?

My bro had the same issues running a sidewinder in his evader when using a 6 cell nimh stick pack. It disappeared when he put his lipos in. Naturally this suggests it's a battery issue, but my new A123 packs are much more capable than my old fried no-name underrated lipo's! surely it's not a battery thing?

Any input would be greaty appreciated :)

Thanks!

Sam