RK05 and TMA-11

I am in the process of adding a TMA-11 tape controller with a TS03 tape drive to my PDP-11/10 system which has a single RK05 drive attached. There no other devices attached. I removed the Unibus terminator out of the RK05 and connected the BC11 cable in it's place. The cable then goes to the TMA-11 controller. The TMA-11 controller does have a terminator as well (ie. it is the end of the Unibus). Previously, the PDP-11/10 and RK05 worked as expected. Now that the TMA-11 controller is connected, the RK05 drive does not spin up. When the 'Load' button is pressed on the RK05, I do hear the door lock solenoid engage, but the drive spin up. If the system is powered down and the cable to the TMA-11 is disconnected, the drive does spin up. Any ideas on why the RK05 would refuse to spin up when connected to the TMA-11? I am just looking for some pointers to narrow my search. Thanks! --barrym