SamyGO

Might it went to CI off in service menu?

Physical damage, lose connection of lvds-tv screen or so. Poorly believable if reason is software related nature. I bet for hardware.

UAKUC ia important. You can not mix firmwares as they are Region dependent. Ending of firmware indicates region this firmware is aimed to. TV either does not accept firmware at all or bricks.

Quite interesting thing. AFAIK not possible on My series.

Possible I have it somewhere. Write me pm as a reminder. Thanks.

Possible TV is not supported by YouTube so that no working widgets

If TV works well, then this means nothing

Very restricted firmware which even isn't rooted. Nothing to be done with this model.

Go ahead.

Search forum for "micom upgrade" and you get your answer.