To fix this problem while waiting for a firmware patch, you can use the following trick:
1. Turn on the Zappiti player.
2. Click the "Settings" button located on the Home Page.
3. Click the "Developer Options" button.
4. Scroll down and activate the "Force GPU Rendering" option.
Note: This trick reduces the problem considerably but does not completely fix it. We are working on it to fix it ASAP. Sorry for the inconvenience.