I have not tried a new cable as the current one runs from the hub up to the loft and down into the room with the computer. Thanks for the advice though.
Back on message... You could get 20m of Cat5e cable for £3.95 off eBay and connect it up just for a test period - useful to have in your "electronics drawer". Also did you see this thread from Errol who was also getting poor speeds on his iMac and it turned out to be a problem in his browser !
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