Gg L85 Gearbox Locked

[Tactical Pith Helmet]

Used my new L85 today for only the second afternoon since I have had it.  Fired a few shots on semi and the gearbox has locked up tight as hell.  Switching to full auto did nothing.  I can hear the motor trying to turn when the trigger is pulled.   I used an 11.1 lipo.

Any ideas or pointers on freeing it up?  

I expect I shall end up sending it back, but if anyone knows a quick fix I would be grateful to know it.