Advice on burning for PAL Dreamcasts ( Flickering problem )

[curious.au]

Hi.

I was wondering if anyone could give me some advice on burning images for my PAL rev 1 Dreamcast. So far, I have burnt two discs for it - Utopia Boot 1.1 and Ikaruga. In both cases, the CD's boot fine, but flicker like crazy once they've passed the Sega Logo area. ( It looks like two or three images are squashed vertically onto the screen, or something like that ) - the result is unplayable, unfortunately.

Ikaruga also throws up with a Disc error, but I suspect this is because I ignored the .nfo file and burnt it with cdi2nero instead of DJ4 - my bad.

So, is this flickering an indication that the DC is spitting out NTSC video that is making my TV throw-up? Can I patch around it ( or am I patching incorrectly? )? Do I need to adjust some parameter on the Television, such as Vertical Hold ( I thought of this after I left the house )? Do I need to lay my fingers on some kind of converter, or a VGA adapter?

I didn't think it was the vertical hold because Bust A Move 4 ( original ) plays fine. Anyway, if anyone has any advice for me, I'd really enjoy it.