Duo-R Video Dropout issue

[maxlords]

So I finally hooked up my Duo-R today and I'm having a video issue. As I am playing, the video and the sound randomly drop out. My Duo-R is SCART modded with a custom SCART cable and hooked up to my TV using a SCART to HDMI convertor set to 1080P. I'm using an older HDMI cable which I suspect might be the culprit, but I'm not sure (and don't have a nicer one spare at the moment). Any other ideas what might cause that? I never had the issue before. I'm also getting a few horizontal rolling yellow/green lines as well. It's definitely not the system, as the CD isn't stuttering and it happened on huCards as well.

Thoughts? Suggestions? I'll change the HDMI cable out sometime shortly to see if that's it of course.

Thanks!