I am not sure if this is a fix for your problem or not, but there is an adjustment in the EXT service menu called "Flicker Adjust". Here is how you access it:
1) Put projector into service menu mode. To accomplish this. First press the power button on the remote breifly, then press the right arrow button to highlight the cancel option, then press the up arrow, then the down arrow, then the up again, then the down again, then press the enter button and the screen should show the EXT Option menu.
2 Select the option for "Ficker adjust" and press enter
3. Write down the reference values for each of the red, green and blue screens that will cycle up as you press the up or down arrows.
4. Adjust the value in each screen using the right or left buttons to a value that minimizes any flickering that you see in the individual color screens. You should be able to get each color (red, green and blue) to be mostly flicker free.
5. Press the return button to return to your normal input signal. If things don't look right, reset the original values that you wrote down before making any changes.
I do not know if this will fix your probklem, but it seems to be worth a shot.