Yes, thanks for the details and tips. I'd installed TT5 over the previous V3 and this must have kept it's bluetooth settings. It worked OK except having to connect the BT manually every time.
Having had to hard-reset and install TT5 again I had to reconfigure the BT, which was painful. Having seen your note about the wired GPS setting I checked out the TT site and found some good instructions at
http://tinyurl.com/dzesy
Having followed this I was able to get working again and now have TT automatically linking with the GPS itself.
There was also a useful article on using complete postcodes in the UK.
