Hi welcome to the forums,
The forums are customer to customer in the first instance, Only the mods (BT) will ask for personal information through a email link. Would you mind posting your Hub stats & BT speed test results this will help all with diagnosis-
To post the full stats from your router
for home hub - 192.168.1.254
Navigate to ADSL Settings or use the A-Z at the top right
Click on More Details and then post the results.
Run BT speed tester and post the results from http://speedtester.bt.com/
If possible it would be best to connect to the BT master socket remove the front plate if possisble and connect to socket this will rule out any telephone/broadband extension wiring also consider the housing of the hub/router as anything electrical can cause problems as these are your responsibility
Noisy line! When making telephone calls, if so this is not good for your broadband, you can check-
Quite line test dial 17070 option 2 and listen - should hear nothing best done with old type analogue phone digital (dect) will do but may have slight hiss If you hear noise- crackling pops etc, report it as a noisy line on your phone, don’t mention broadband, Bt Faults on 151.
tell me im daft if you want but after 3 engineers have been should they not have checked this stuff .
post the full results from http://speedtester.bt.com/
Have you tried connecting to the test socket at the rear of the master socket
Have you tried the quiet line test? - dial 17070 option 2 - should hear nothing - best done with a corded phone. if cordless phone you may hear a 'dull hum' which is normal
also you could try the hints given by poster RogerB in this link they may help http://community.bt.com/t5/BB-in-Home/Poor-Broadband-speed/m-p/14217#M8397
Then someone here may be able to help and offer more advice.
This is a customer to customer self help forum the only BT presence here are the forum moderators