Hmmm - all of my boards have come via Farnell.
Perhaps it’s not worth me getting another one to try after all?
many4tunetellers, did you realise you posted 3 times?
Why not send one boards in under RMA and let us look at it.? If it works here, that can send us in a the right direction.
Gerald
Sounds good to me 
RMA request sent. I may be able to get it in the post today.
Thanks Gerald.
Wait to hear back from the RMA folks before you ship the board.
Gerald
Sorry about that I had no indication the the first 2 had been sent unil I moved to google groups.
.
My RMA authorisation came through this morning - it seems my request went into spam and has just been found fortunately.
I’m shipping one of my three boards to Texas for investigation - not sure how long it will take from the UK.
Fingers crossed they find something useful to all of us with the problem.