I haven't got an answer as to why noise on your line effected the TiVo's, but not the PC (though you said were also having issues with the forum). Your modem should handle these issues (assuming that they were only cabling related and not ISP), and the TiVo should have similar results to your pc as they are both using the same ethernet connection.
But glad that you have at least resolved that part.
Now with your IR problems, are you using IR wands or relying on the inbuilt blaster?
Peter.
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