[RC-Monster Mike]

The 1930/5 will be spinning at over 80000 rpms on that voltage (so yes, it is too high voltage if you want to have the motor for a while!). The controller should still handle it, though. Perhaps you could describe the sound a little better to me. Also, did you change the gearing when you added all those cells? Lower gearing woiuld definately be necessary. Another thing to try is a real receiver pack (5 cell nimh or nicad). the aa batteries are considerably less than ideal.