Connecting Sonar X1 with Behringer BCF2000

Hi all. I'm trying to set up my BCF2000 to work with Sonar in Mackie emulation mode. I've followed every tutorial that I could find to the letter, but the device still fails to connect.

I've installed the latest version of the drivers on my PC. I've successfully updated the firmware to v1.10. I've hooked it up via USB, and the USB light is lit. I've started the device up in Mackie emulation mode. I've added the Mackie control surface in Sonar. Sonar is receiving MIDI messages from the device, so I know that they are physically communicating. However, the display on the BCF2000 shows "NCSo", while Sonar just shows "connecting", and it never actually fully connects.

I did manage to get it to connect correctly one single time, seemingly at random, without doing anything different that I was aware of. The display on the BCF2000 changed to "Tr", Sonar said it had connected, and bi-directional control with the sliders was established. After that, I could restart Sonar and it would connect correctly every time. However, as soon as I turned off the BCF2000 and turned it back on again, it failed to connect from that point on, and I haven't managed to get it working again since.

I've spent a whole day trying to troubleshoot this, and I'm now at my wits end, and completely out of ideas to try. I'd be very grateful if anyone has any thoughts on what could be going wrong!