Sorry to say but from my experiences..

50% A cpu failure, mostly only to repair with a new cpu.
35% Related to the cpu, but then a print track or bad solder track from the cpu.
10% Hdmi cable, or issue with the tv hdmi connector.
2% Software related.
1% One of the diodes, D600/D601/D602
1% Hdmi connector failure.
1% Other unknown cause.

But mostly it is the cpu, and mostly fixed after a new cpu.
For more information, see this topic for a schematic.
Dm800se Hdmi information
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Doing nothing leads to nothing.

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Will be given here, or on the jb8a8f8 forum and I prefer it in English.
Johnny B.

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