Toshiba PCX5000 (Cable Broadcast failing)

And exactly how did you determine that it's not the most likely cause?
What test equipment did you use? What parts did you replace? Did you
disconnect the inside cabling prior to the first splitter, and try the
modem there?

It's far more likely that the issue is your inside cabling than anything
else -- bad splitters being ahead of bad coax. Second on the list,
behind both sub-issues of the first, is plant problems. The modem being
the issue comes in at a distant third. A very distant third.

In the unlikely event that it is the modem, the only fix is to replace
it.

--
Warren H.

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