There should be no need to reload the software..... but if you've already started...... finish it.
On my web site> music & recording> MC4/5> scroll down and look at the stuff there for working with TTS. It might help you a bit if you're not real familiar with TTS and synths.
Be sure you have a midi track in place and it's assigned to the right TTS channel and track and you have a viable patch and bank selected.
One tiny thing out of place or directed incorrectly will result in no sound.
I occasionally have comm issues between the computer and the interface and a complete reboot of BOTH from a cold start is sometimes needed to set things right.
Also check that you do not have the track muted or the volume pulled all the way down.... I can not remember how many times I have rebooted only to eventually track the "no sound" issue to a fader all the way down.
Load a different synth such as Cakewalk Sound center. It comes up running a default sound sample unlike TTS where you have to load things and assign things. I found TTS to be a very capable and at times, especially at first, a bit hard to understand. CSC is a much simpler synth in regard to making it work.
Be sure the sound card is working by playing an audio track.
Maybe that will point you in the right direction.