mamba max problem

[rcsammy]

i have two MMs which i run and have problems with
the first is in my TC3 on a VXL motor on 3S, it will go forwards fine but i have no brake and no reverse, i have tried resetting all settings, and an older firmware version, i tried to calibrate it and it takes the forwards setting fine but i get a flashing red light after that and it wont accept any reverse or brake settings

the second is in my rustler on a Neu 1506 on 3S, i was just running round on some grass earlier today, hardly into the run and it just stopped, no forwards or reverse
when first turned on the motor will run for a few seconds then it dies again, cant work out whats wrong
tried a different motor and its the same and i have tried a different battery too

thanks for any help