TV Issues Resolved

As I suspected, the problem with the output to the TV was too many conversions of the signal, once I plugged in an actual DVI cable into the TV, the Mac Mini sprang to life on the TV. So I now have DVI-D running at 1280 x 720 @ 60hz (essentially 720p HDTV resolution).

Just in case anyone is wondering about the quality of the Apple converter here, I can pretty much definitively say that it was not the problem – it worked just fine when I plugged it into my LCD multi monitors and, having built up a collection of DVI-VGA converters over the years, I tried a few more – all with the same result.

The moral of the story is – spend the extra $15 and get a proper DVI cable, it will be worth it :)