Solved Traktor Pro (Windows) crashes on exit when wireless MIDI device is not connected

Hello, after suffering many headaches over this problem, I am archiving the solution here.

I recently purchased the CME WIDI UHost for wirelessly connecting my DJ controller to Traktor. I am using the Faderfox DJ4 controller. To improve Bluetooth MIDI performance on Windows with the UHost, I installed the KORG BLE-MIDI Driver.

The WIDI UHost creates MIDI In/Out ports that are ALWAYS available, regardless of whether a device is connected or not. Since Traktor automatically connects to the previously used MIDI ports, it will default to the UHost MIDI ports even when there is no device (see picture of Traktor MIDI settings).

If no MIDI device is connected during the time Traktor is running, Traktor will crash on exit (see picture of error message). I am guessing that Traktor sends a MIDI message to the connected device before closing, but fails in this scenario.

There are 2 solutions: (1) Set the MIDI In/Out ports to 'None'; or (2) Connect a device to Traktor via the UHost. You may need to set the MIDI ports to 'None' and back to 'UHost' to make sure Traktor establishes a connection.

Aside from this problem, the WIDI UHost works well and has low latency. I added a picture of my setup with the Faderfox DJ4 (I stuck a small powerbank underneath with velcro to power the UHost and the controller). Keep in mind that you cannot use a controller's soundcard through the UHost as it only transmits MIDI.

For completeness, here is my system info:
- Traktor Pro 3.5.2.299
- Windows 11 Pro (x64) v.10.0.22000 Build 22000

Happy New Year!