I had another go and for some reason it worked this time, still not sure why but thanks for the help!

I had the motors running briefly but all of a sudden they started juddering and stalling, all the warning lights on the RX and Servo went off and it just ground to halt, while the motors make an odd popping sound, I tried restarting it and whatnot but it's doing the same, just clicking away and the motors barely rotating.