Hiya Curt
Thanks for the reply.
Yes, play both at the same time. Say I am playing a registration from the SD40 with 4 instruments to navigate to on the screen. since I can play most anything by ear on the harmonica, I have a DM48 wind controller to jump to for embellished riffs etc.

Technically, both are on ch1, so when I jump to the DM48, I have to unplug the Controller and plug in the wind controller, naturally, since they are both on the same channel. Both are readily recognized and work perfectly.
I hope this helps.
Bernie