In RB you would likely need to copy the track to another blank track, then leave one assigned to the default synth and the other you would use right-click track - Port - then select a different port to send that particular track out to (the SK2 port).
from memory ... I can check it later
most people do not want to hear the cheesy computer sound along with the nice synth sound

I do not work here, but the benefits are still awesome
Make your sound your own!