I'm new to ARRMA. And just getting back to RC world. I have a granite 4x4 mega. Only thing I have is a 2s lipo battery still brushed. I was playing here few weeks ago and it started acting sluggish finally stalled out and motor burned up. Being less then 3 weeks old arrma replaced the motor. I put the motor in yesterday to I get it out. 15 mins into playing same thing. Sluggish and smoke rolled out of the new motor. Any ideals??