Hi Folks:
Thanks so much for all the pointers. Yes, I've looked at pretty much every issue above (VTA, distance to spindle,leveling, tracking force, cartridge loading, positioning of cartridge, wiring etc), and I think it's really something faulty rather than more tweaking. Although, my current set up has the turntable quite high (on the top of a five shelfh rack),and while level, is likley not very rigid. With so much stuff in my room, it's proven difficult to get better positioning of the table. I think that placement, while important, wouldn't really make the improvement I think I should hear though - I think it's something else. Anyway, once I get my Shelter back, I'll let you know how things go.
Tek2000 - many thnanks for offering to meet up to troubleshoot. Yes, that would be great. I'll be in touch when I get Shelter back. I'd like to see what others may think of my system too (apart from the YBA, Teres and Supratek, I have Audio Physic Virgo MkII speakers, Blue Circle BC2 hybrid monoblocks with FIM Gold Power Cords, other cabling is 47Labs OTA Sakura throughout). The Supratek really is a gem, by the way - it killed the Sonic Frontiers Line 3 I had, which I was happy with till the Supratek came along. I can't wait to see what Mick builds next. Cheers.