Help! Please! Fuzzy Picture

Please help. I have recently bought a Goodmans X Pro DVD rewriter (GDVD 301R). I have conected it using two leads to the TV and NTL Cable box (i.e. NTL >> DVD >> TV plus NTL >> TV). The picture is fine recording from terestrial TV and playback is (so the DVD works okay). Watching the NTL live is fine (so the Cable works okay). But I can’t get a decent picture from the NTL via the DVD and therefore can’t record. Has anyone got any bright ideas. Thanks