Test socket abandoned, worse than when plugged into the normal socket I use for it. Strange!
Looking at the router stats it seems to be running quite nicely then getting a lots of errors and falling over.
Lots of the errors are uncorrectable , so looks like a line fault to me.
You could try this to see if the BB stops dropping.
Plug a known good working corded phone into the test point (via a filter) and then plug the router (ideally a BTHH - for proof to BT) into the filter (with the router switched off). Depending on what call package you're on (unlimited anytime or evening and w/end) make a phone call. Then switch the router on. Stay on the phone for almost an hour (as it's good to talk!) and see if the router drops the BB during that time. If it doesn't drop then it backs up the idea that you've got a bad connection/line fault between the socket and exchange.
An engineer called this afternoon. After a lot of testing at the test socket he changed the connections at the cabinet. He then went to the exchange and changed over the equipment the line was connected to.
Been connected about 2 hours without a dropout so lets hope its now fixed.
Connection lasted for 8Hrs. Synced again at slightly higher rate and as now been up for over 12Hrs.
Been told by forum mod that the line is back in training for 10 days so will see how it goes.
So looks like the engineer did a good job and I must say he was very thorough and professional.
Thanks to BT the mods and openreach for all their help.