Pitch bend doesn't work with Octatrack

For some reason when I am hooked up to the Octatrack via MIDI, my OP1 doesn’t do pitch bends using the shift and arrow keys. Unplug the USB cable or switch off the OT and it works fine. Any suggestions as to why?

Just thinking out loud… The op1 might automatically disconnect local control when routed through usb midi and messages to its own keys may be relayed from the OT out. Some of the midi parameters on the OT need their encoders pressed down (or function+encoder click) to be enabled. It’s something strange like that I always stumble over.

@Lymtronics Good suggestion but sadly not, I didn't think that would be the case mind you because my OP-1 is connected via a Kenton USB host and yet works when the OT is off but the OP-1 still plugged into the Kenton so it would think it was connected via MIDI.