in the MIDI setup dialog form, is the box checked for
[x] USE VSTi/DXi synth?

in my experience with RB when trying to send MIDI to an external device, if you have Midi output redirected to a soft synth, the external device won't ever receive the commands you're sending.

Even if you specifically send it to the device via the right click menu, it won't work if the box is checked in the MIDI dialog box


If you need to control external devices with MIDI *AND* use soft synths, you should uncheck the aforementioned box in the MIDI dialog, and define the soft synths individually in the tracks right click menu.