Update:
So after a factory reset of the MX box running 4.2
Fresh install of kodi, same problem. Sound with no picture. The icons are visible like play, stop, ff, rw etc.... But just no image. Tried changing acceleration settings. No joy. Tried all the box settings in regards to HDMI detection, no joy.
This problem only began when he upgraded to Jarvis 16. Running on 15.2 was fine so it leads me to think that something is not compatible somewhere. Even changed the HDMI cable for good measure.
Considering upgrading firmware, Any suggestions as to where I can find the right information for this if all other options are exhausted?
Thanks