OK people so part of upgrading my home network I've upgrade my router to the WRT160N, my WRT54GS is now sitting idly after 4 years of constant rock solid service.
I've modded my WRT160N with 2x 10 db antennas and get excellent signal three floors up (in the attic), which I am quite pleased with.
I also followed the advice of performing a quiet line test, which seems fine - and also plugging my modem directly into the test socket. My speed as a results jumped almost 4mbps! The extensions were causing problems (probably due to interference and impedance - wire just sitting there is just a big antenna for microwaves!)
So I've lopped off the extension from the main faceplate as I don't need it anymore.
However I am trying to increase the speed further, will installing a iPlate increase the speed? Our main socket is the old type (about 10/15 years old min!) with a 'T' inside a circle and the right side of the T is two dots.