Have you tried the S-Video input on your 5500/Tuner?

I still think it'd be better to just replace the stock Cartridge Loader with a cartridge faced, skinny-tray Loader DVD Player. Use an external CD if necessary, but what the heck can you do with that POS MacTV/CC board that needs CD support.That has to be one of the very worst offerings ever. The DVD plays Music CDs just fine.