If you go to Options-Preferences-MIDI devices, you can see what synth is being used, do you have the Re-Route MIDI box checked (top image)?

If so check the synth itself for MIDI channel routing to patch assignments for playback.

Hopefully the images below help. First image is how to assign the default synth, second is how to assign a patch to a given MIDI channel on that default synth. I used the Coyote interface as an example for the second.

Attached Files (Click to download or enlarge) (Only available when you are logged in)
PT-DefaultSynth.jpg (81.39 KB, 70 downloads)
PT-PatchAssign.jpg (89.77 KB, 68 downloads)

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