I too have issues with 800V4 especially hard locking onto HDMI sources.It can often try many times to lock with relays clicking in and out but often it just ends up with a blank green screen. Unplugging the HDMI cable and reinserting it normally cures the problem. Meridian are aware of this. I know that a new version of software for the 800 is iminent and this will address a number of these issues. I think we are looking between 2-4 weeks for an unoffical launch. You will need to pester your dealer if you want this software before it's offically posted.

Yours Nick