E-Flight 160 motor/Castle Phoenix Ice HV 120
 

Im having a tough time with this motor esc combo....I have run this many times in the past but now I am getting a motor "growl" with forward/reverse and "grinding" as I increase throttle. I am using 2 6S 6600 MaH packs in parallel. I have updated the Castle firmware to current version and reset all the ESC to factory default. Nothing. The ESC is not damaged,,,before I send this back to Castle, maybe there is something I have overlooked?