Hi David thanks for the detailed description.

I have got my head around the signal flow now and it all makes sense.

The only issue I have is that when I am sending to both midi channels 1 (main instrument) and midi channel 2 (linked instrument) it will only play one or the other.

I have created two separate midi outs in Logic X and I am sending midi data to channel 1 + channel 2 on the Polaris and it only play out one of the instruments. I have also tried sending an ALL channels message which should make the Polaris play on midi channel 1 and 2 but this is not working. Somewhere down the line it is refusing to receive two channels of information.