As I said, the 6 ft HDMI had the same problems with my first ML500 which is why I chose to return it. Just a follow-up with my replacement ML500; still no connection issues with the 25 ft HDMI. I also ordered a 50 ft Blue Rigger brand HDMI cable and have not had any connection issues with it during playback (that is one thick cable). I am NOT using a repeater or booster but I may pick one up just to see if it helps in the initial connecting to sources quicker.
I still like this projector a lot and can't wait for my ceiling mount to arrive. I find myself re-watching movies I haven't seen in a while and it's like seeing them in a theater for the first time
Off topic, I am also enjoying my new Yamaha HTR7065 AVR that replaced my still functioning 12 year old Pioneer AVR without HDMI connections. The new Yamaha really brought new life and clarity to my speakers and allows for the necessary single HDMI run for install.