Sorry to disappoint you, Geoff103, but that's the same line I was given over a year ago.
It took a year for them to fix my Caller Display.
Try an email direct to the CEO?
I recently discovered the same Caller ID fault (ie it doesn't work). As far as I can tell its appearance coincided with a major fault on the line. That was rectified within a couple of days but the Caller ID problem remains.
Contacting BT helpline took them 15-20 mins of asking/checking around to come up with the answer..... It's a national problem which we expect to be fixed soon so don't call us we'll contact you when it is!! Of course I took that in good faith, but it seems since finding this thread that the BT contact would just have been relieved at my gullibility and happy to move on to "solving" their next problem.
Contacted BT via online chat again. 10 mins of "performing tests" and the inevitable " try *#234# and tell me what it says".... it says the same as last week ie Caller's ID will be displayed. Another "please wait" of 5 mins and the message is that the issue has been raised with Openreach and they give a date of 26/11/2015 for a fix. On pressing I even get a job reference which I am assured can be tracked on the BT faults webpage. Sounds a familiar story. I expect I'll be online with them again on the 27th!
Closure: mea culpa (perhaps, but I was misled by BT "help")
Openreach turned up on time to investigate. All tests on their equipment showed Caller ID data was being received. **bleep**, that must mean it's my hands-free equipment or even worse the house wiring. As he left, the engineer commented - one last thing you might try is plugging the hands-free base station directly into the main inlet socket in the house (as opposed to in a room extension). OK, thanks. **bleep** again, Caller ID does work there! Went back to all room extensions - still no good anywhere. Back to main socket - yes still OK (repeated several times). Swapped broadband/phone filters - no difference. As I was contemplating how to live with the base station connected at the main input I glanced at the phone signal connector into the base station - the only connection I had yet to unplug. Take it out - connections look OK and clean, plug back in - Caller ID works everywhere!
OK, probably a one-off solution to a one-off problem (how I hate unreproducible symptoms!) - but note to BT 'help-line consultants':
Save yourselves and some customers time and frustration -
1) suggest (or remind) customers to check/re-seat all possible connectors (I know, I know it should be a DIY first port of call)
2) Suggest the 'connect to main socket' test
3) Avoid the "it's a national problem" patter which may be a total red-herring even if it does exist 'somewhere'
Question: If a bad connection at the base station itself was the cause, can anyone explain why Caller ID would work when the base station was at the main input socket but not on any of the house extensions? Of course there still remains the possibility of a conspiracy - someone was still playing with equipment upstream and the fact that my fiddling produced a result when it did was just an amazing temporal coincidence.... stuff happens!!
Wow - I see BT forums are super sensitive on vocabulary. The ** bleep** was only Delta, Alpha, Mike, November. Good to maintain standards though I suppose!
Thats going to cost you for the visit, as there was nothing wrong.
The CLI data burst is very short and easily distorted by a bad connection. The level of signal would have been highter at the master socket, which is why it may have worked better.