I am actually having the same problem but in my case it works on a 720p LCD and not on a 1080p LCD. I’ve tried everything I can think of. Forcing HDMI, forcing VGA, changing/trying different screen resolutions, X and Y configuration. The only way I could get 1080p TV to work was to remove PSX/N64 roms. Depending on which settings I try, sometimes I get a frozen blinking ES splash screen and other times I get a black screen that I can launch games from but cannot see what I’m choosing.
I’d really like to find a resolution to this annoying problem.