Power shutdown with xbee

Hi

I have a strange problem with my xbee setup. I am using a Mac and Mountain Lion, Coolterm for sending commands to my rover xbee. I have uploaded the wsda sketch from arduino and it seems that I can send two commands e.g forward, backward from my keyboard and then on the third command power shuts down. I am using the provided lipo from robotshop to power up my rover. Any idea of what is going on?

Cheers
DT

I have now resolved this issue. It seems it was the Lipo that came with the kit. Although I tried desperately to charge it never managed to get fully charged. Anyway as soon as I installed AA batteries the rover started working properly.