Why should it be nearer 6 Mbps? The profile is determined by the line speed not the other way round.

Edited by deleted (Tue 04-Apr-17 20:00:27)

If you are now getting 6.97 Mbps then that is good, and shows that your problem is the wiring Fitting a VDSL Interstitial faceplate will resolve the problem with the extensions by isolating them from the broadband signal

If the profile is 7.15Mbps then the line speed is higher than that. Speed tests in normal circumstances then would be in the high 6's - but there could be congestion on the provider or there could be a lot of errors that are slowing the line, or it could be the line sync is flapping but the profile wouldn't normally stay high.

OP needs to post information about speed tests and the sync rates at the time of the speed test in order to understand what is going on here.