You may have a bad cell. Try putting your charger on Nimh, drop it down to 1 amp or so, and let it run for a bit until it gets over the 3.x cell votage.
Losi 8T 1.0, Savage Flux - XL style, LST XXL, Muggy, 3.3 E-Revo Conversion and sitting outside 425hp, 831 Tq Dodge Ram Turbo Diesel. It SMOKES