I'm considering getting Freeview HD, and I currently have a VHF/UHF combination aerial. I'm in a "very likely" reception area for FVHD, however when watching FTA channels from the aerial Maori TV and Prime are both snowy and in Prime's case, sound is not so good. 1,2,3 and 4 are all fine.

Will FVHD reception be any good, or does this mean I'll need a new UHF aerial? Or does my current setup need tuning?

Thanks for your help.