I bought my Freesat Humax box in 2008 just before Xmas and have had trouble free use from it until today.
Now, when I switch it on, the HDMI works for about 30 seconds after booting and then the screen turns green. Restarting the box has the same effect - boots ok, screen and sound comes on and then green screen with no sound after about 30 seconds.
I have done a factory reset, tried a different HDMI cable, tried another HDMI device in the same port on the tv, changed the picture from 1080 to the other options but with no change. I have also powered down the box and left it for about 30 seconds - again with no effect.
I plugged in a scart lead and that works fine, but the HDMI fails repeatedly.
Is this an error others have had and does anyone know of any ways of rectifying the problem?
Thanks in advance for any help.

Try setting the box to non-Freesat mode, and see if it still does it.

Thanks for the reply, Nigel. Switched to non-Freesat mode but the same thing happens.

The reason for trying it is due to HDCP, which usually causes these kinds of problems (and can be box or TV) - in non-Freesat mode there's no HDCP (as far as I know), so it eliminates that as a problem.

As another HDMI source works OK, it leaves the box the most likely cause.