I bought some of these to convert the RCA from my consoles to the BNC terminal board on my PWD6. At first it seemed ok but I have noticed some feint lines running horizontally across the picture. I've read briefly that using these converters can cause an impedance mismatch. Are there any superior adapters I could try? The adapters from TVcables don't mention ohm rating at all. The other possibility was to purchase the TU-PT600B tuner box with RCA in (no-one has any stock of the RCA terminal boards) and then sell my BNC and Scart boards (I use the DSUB for SKY+/DVD). The question here is: I've read that to use the tuner box you cannot use any of the other terminal board slots which is fine. Can you still use the built in DSUB connection when using the tuner box? Thanks in advance.