Why does Reason sometimes lose it's MIDI connection when I switch to another...

Why does Reason sometimes lose it's MIDI connection when I switch to another MIDI application?

It has turned out that Reason can lose contact with OMS if OMS is not set to run in the background. To fix it, do this:
1. Close Reason
2. Open the OMS setup application
3. In Edit -> OMS MIDI setup, enable the 'Run MIDI in background' option.
4. Save and quit OMS setup
5. Launch Reason again.

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