Hi All
FYI, I took the main board off and wafted a Heat Gun around the parts
which I regarded as suspect - mainly the Zoran chip, RAM and Flash. Put it
all back together and ... whaddya know? It's been working fine now, for a
week or so. Only had light use, and of course it might go wrong at any time,
but I'm pleased for now.

I dunno if I reflowed a dodgy solder joint, or dried off something, or blew
a spec of something away ... but I'm happy to mark this one down as a win.
Thanks for your previous thoughts on the matter.

Cheers
J^n