Extension Wires

[tehidyman]

Some years ago I had an extension put in for my internet computer (by a professional- ex BT).  In an attempt to reduce my noise  I looked in the extension socket today and found 6 wires connected.  I have removed those from terminal 3 & 4 (as advised elsewhere on this forum) to cut out the bell wire but wonder if disconnecting wires to 1 & 6 might also help to reduce noise.
Second question. Should all the disconnected wires be trimmed off near the cable sheath?

The fluctuations in my noise margin of usually  plus or minus two db (around 10) within a three minute interval stopped and changed to dead steady at 7db as soon as I removed the extension box cover and replaced the 'plug', and my sync jumped from 2464 to 4832kbps, line attenuation was a constant 50 but went up to 53db. I have a Netgear 834 v3 with updated firmware. Using RouterStats as monitor.

[Rik]

Disconnect everything but terminals 2 & 5, making sure that they are a pair, eg blue/white and white blue. Do this at both ends of the cable. Roll the disconnected cables back neatly out of the way, use a piece of insulation tape if you want to.