Hello Kitz and Coolsnakeman
Thank you both for your replies. I did a 17070 test on the line which was OK. I have since checked my neighbours Livebox on my line and again it was OK. Having cycled round the village numerous times I eventually found a B T engineer and his opinion was also that the fault was in the exchange, possibly jumpering as per one of your suggestions. We have reported all this, including your comments, to Orange but it is difficult to know if they really take it on board and will create a job sheet for the exchange to be checked - they just don't want to pay B T to do the work. Orange have now been told that it needs fixing before the end of the month otherwise it will be MAC codes and move to B T.
I like your suggestion that this could be caused by LLUing our exchange, that could possibly be the good news if that is happening, we can only hope because it should reduce the monthly cost.
Thanks so much for all your help. I will post the outcome.
Mike