Fastrack 650 cutting problem

We have a Gerber Fastrack 650 and are using it with Flexi 7.5 on a Mac. The machine isn't cutting properly--on text, there are little gaps around the curves (like the inside of an "a" or "o", etc. Has anyone experienced such problems? We can't figure out if it's the plotter or an incompatibility between the plotter and Flexi. Help!
Elise