I don't think the interface would have anything to do with this issue.

Essentially, the interface deals with the audio coming out of the DAW. Whatever audio is being sent out goes to the interface and you can hear it. The interface is not involved in the process of reading and interpreting the data and making the sounds. Sound comes usually from the master buss output. Since MIDI is data, it has to be routed to a synth which plays the samples and provides that synth audio output to the master buss.

You mentioned you're on a new machine so I would check your software settings in the DAW and be sure you have your midi routed to the proper synth on the correct midi channel and that the synth output is routed to the proper place as well to be able to hear it.

One thing you should try if you haven't already done so is to freeze or render the midi to audio. I use Cakewalk and when i freeze the synth, it converts it to audio. I can see the wave form and it should play like any other wave file at that point. If it doesn't, you need to check your routing. And be sure you don't have anything muted in either the synth or the tracks.

You can find my music at:
www.herbhartley.com
Add nothing that adds nothing to the music.
You can make excuses or you can make progress but not both.

The magic you are looking for is in the work you are avoiding.