in order for the forum members to help please can you post the adsl stats from your router may need to 'show detail' to get all stats (if hub enter 192.168.1.254 in your browser and navigate to adsl or use a-z, if netgear enter 192.168.0.1) and run btspeedtester (MAC users may have problems) bt speedtester and post the results .
are you connected directly via a filter to the NTE5 master or test socket or to somewhere else? Is the master the only phone socket in your home?
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
Someone may then be able to offer help/assistance/suggestions to your problem
Speedtester is 11.25 Down, 0.92 Up and connected to the master socket. This speed has been constant as i said for months but as BT advertised a higher estimated speed as of yesterday I'm intrigued as to why.
with your attenuation a connection speed of about 16mb is what I would expect. with your stats your noise margin is normal 6db so I cannot see where increase will come from
what about connection - test or master? other sockets in your home?
quiet line test?