TMS320F28069M: Motor Instability in SpinTac velocity control

Part Number:TMS320F28069M

I am using a 8301D board with a F28069 control card. I have all estimator functions turned off, just RunIdentify, and EnableSys are on from startup and all values are initialized to init values. When I run the motor, about 50% of the time, in a seemingly random pattern, I can give the motor a positive velocity(any positive velocity) with a normal acceleration, then the motor will spin in reverse at max velocity. The code is based on lab 12b using the QEP as feedback for the control. I have also tested the lab code with the same results, it sometimes spins in reverse at max velocity.