Should work, UNI receivers bind OK for me using a MPM.
When you power a UNI Rx on in bind mode, the red LED should be on, but blink off every half a second (when it changes to another possible protocol).
The MPM, when binding, often only stays in binding mode for a short time. This may not be long enough for UNI to detect the required protocol and carry out the tuning function.
Try:
Power the Rx on in binding mode.
Check the red LED is blinking off every half a second.
Now put the Tx into bind mode, fine tuning set to 0. The Rx should stop blinking the red LED at some point indicating it has detected the correct protocol. If it doesn't stop blinking then change the fine tuning on the Tx, try both +30 and -30.
Once the red LED has stopped blinking, if the Tx drops out of bind mode, just restart bind mode. Also try moving the Tx further away. The Rx needs to receive quite a few packets in order to establish the required tuning value, this may take some time (several seconds). When bind completes, the red LED is off and the green LED flashes.
MIke