I'm trying to connect my dvd-r to charter cable in parallel to my charter cable box. I just want to record some events off of basic cable service while my wife can watch what she wants. I suspect charter cable is pinging this line and picking up 2 devices, because after about 5 minutes with this setup my tv went blank, but the dvd-r picture was still on. I disconnected the dvd-r, and my tv picture came back. Is there like a one-way pass filter I can put inline with my dvd-r, hopefully to make charter believe it's looking at one device? Currently I have the the dvd-r in lne with the cable box, with a splitter and a/b switch I can watch basic while recording from the cable box, which is the opposite of what I want. am I missing something simple?