Yes, that makes sense and I should of realized what was happening earlier. So you do need to release the driver from the first BB instance, and unplugging is one way to do that.

There is another way I thought of, but you need to route different MIDI channels to each BB, and you need to change the channel your keyboard is using between songs. There are a variety of free MIDI utilities out there. I haven't done a thorough check for what the most current utilities are, but one that's been around a long time is MIDI Ox. This program allows you to select your USB keyboard for MIDI input, and then route specific channels to specific MIDI outputs. You'll also need to install a 'virtual MIDI cable' which allows you to connect two applications together and pipe MIDI data between them. MIDI Yoke was typically used for this purpose.

I did try this out and it worked for me. The programs are a little old though, and I'm not sure if they work on 64-bit - so your mileage may vary. I used MIDI Yoke 1 for the first BB, and MIDI Yoke 2 for the second BB. I routed all channels except channel 9 to BB1, and all channels except 5 to BB2. Then all I needed to do was select either channel 9 or 5 on my keyboard to determine which BB I was playing through.

Andrew
PG Music Inc.