I recently acquired the FB9 (non-Gold edition) unit, and am experiencing an issue with 2-player mode on Space Invaders in which when the 2nd player is active, moving the joystick to the left causes the game to exit to the menu. I replaced the game for an exchange, and same issue exists.
ATGames replied to my email, stating that they are aware of the issue and are working on a firmware patch. I am hoping the fix - if/when complete - can be applied via the SD card.
Just wanted to post this, and see if anyone else has experienced this issue.