It sounds like its dithering the colors down. Flex apps
usually need the full 24-bit color space due to the smooth
gradients, shadow effects, and antialiasing used. If your projector
isn't set for this mode (a.k.a. 16.7 million colors) or can't
really display that many colors (as with a lot of LCDs) all these
colors will get dithered, giving the grainy effect you're seeing.
If you can't replace or adjust the projector to fix this, you
may be able to dial back some of the effects listed above to give
the projector an easier time.
Thanks for the response. However, it turned out that the
picture was grainy because my sales person was projecting onto a
the white office drywall. When he stared projecting onto an actual
projector white screen the graininess disappeared.