So after going through the rigmarole of swapping my HTPC over to XP pro from W2K and then switching half the settings off to get it working nicely. I install SP2. Theatertek promptly stops passing sound correctly after the dvd menu! Luckily I used Acronis trueimage to image the boot disc beforehand and all is now well. I'm not too bothered as I know TT 2.0 will be along in a couple of weeks anyway which gives another opportunity to install SP2 and see if it works. Ah well I'll just have to watercool the HTPC in the meantime!