See the spektrum forum as they have a lot of info on this issue.
It is likely to be related to voltage drop with the massive power uptake of BL. Esp. heavier offroad vehicles are prone to this like my specially weighted T3 for oval racing. Capacitor is a likely fix. This assumes the issue is nothing broken in the unit. Also, you can always call Novak. Good tech support, although you might need to be on the phone a bit to get through.