Patches won't play audio on newer tracks unless I exit and restart.

Hello, I have the most recent version of S1 3 Pro. Ruing on a Dell laptop with Win7 Pro 64bit. 4GB ram. 500GB free disk space. I have a tune with about 24 midi tracks and 4 audio tracks. When I add an additional midi track and select the patch, I don't get any audio. I do see activity on the track when I press a key, just no audio. Usually if I save and exit, then restart S1 I will get audio on the the new track. However, if I change the patch, again no audio on that track. All other tracks do have audio.

Looking at the performance dialog box, I have plenty of CPU. RAM is about 75% utilized. I know 4GB is not much, but I don't have a whole lot going on in the Midi tracks. Is this a resource problem or am I doing something wrong.

A side question, is CinePerc compatible with S1?

Thank you for your time.

Deis