I have been able to power the Pro-4 with the PUC+ which can be powered by batteries or external power. I have been sending MPE to Roli Seaboard 5 D app in both stand alone and the Noise Au3 plug in using AUM as a host. Too bad the PUC+ is out of production as this is the only BT LE wireless solution that I know of that will work with the Pro-4. Batteries drain too quickly and only last for less than an hour. External power is the way to go. Had no issue with batteries with QuNexis or 12 Step so the PRO-4 must require much more power.