Easily done RONSKI! I changed out my Mk1 filter for a Mk3 and my noise dropped a couple of dB but the attenuation went up slightly. Probably the opposite of what I was looking for? I did notice there are A and B connections on the filtered faceplate however. Would I be better connecting my line to those rather than the A, and B in the NTE5a itself? (if I were able to that is).
BT Infinity 2 - Predicted speed 54.7Mbps down/15.7Mbps up. Actual speed 42Mbps down/4.5Mbps up...

Left BT as they were poor...
Now with Sky Fibre - 37.5Mbps down, 9.5Mbps up