In article ,
Peter Crosland wrote:
Owain is correct Dave. You will find some very knowledgeable people on
the uk.tech.digital-tv group.

Many of whom also read this group. ;-)

The key to getting an answer to all these sort of things is stating the
problem clearly.

The OP sort of hasn't. I've tried to answer his query as I interpret it.

--
*Never put off until tomorrow what you can avoid altogether *

Dave Plowman London SW
To e-mail, change noise into sound.