Aha ! ;

Disconnection the SDA line to the jungle stops the problem.

I have reconnected it and thusfar have disconnected everything I could
find on those lines (SDA1 and SCL1) to no avail. Neither print that I
have matches, but between the two of them I got enough on the chipset
to proceed. There is some kind of "level shifter" circuit between
SDA/SCL1 and 2 so I copmpletely isolated them. All of this didn't
affect the problem. I even disconnected the tuners and sure enough, the
snow was blinking out every eight seconds.

There is a rather large "OSD processing IC" something 90091 (MB ?)
which I DLed the datasheet for but was having a hard time IDing the
SCA/SDL, I think it's processed partly somewhere else, but I did lift
the pins of all the Vccs to it but it still didn't fix it.

I think on my next runin with this dog I'll actually disconnect the
SDA1 pin from the micro. The reason that I didn't head for the EPROM is
that it does not share the SDA/SCL and there is no constant activity on
the bus. Of course it could be telling the micro to do something wrong,
so if the SDA from the micro interrupted stops it, it probably is the
EPROM.

Next time around it'll be another thread, we're going to get some money
made the reat of the week if possible.

Thanks again.

JURB