HV servo pulsing?

[JAILBIRD]

I just got my rig built and the servo is doing something strange. When I turn the wheel on the TX the servo pulses. It repeatedly moves a few degrees back and forth. When I let go of the wheel the servo seems to center fine. Electronics are a DX3R, Losi RX, MMP SCT, and a Hitec 7950TH. I haven't plugged the MMP into a Castle Link yet to make any adjustments. I'm using a fresh charged 3s battery. Does anybody have any thoughts as to what's happening? Thanks.

-JB