MichaelNZ: It has now been about 3 weeks since this discussion, I have left the router on 24/7 and latency is still at 26-27ms to ISP. How much longer should I wait before raising a complaint?
Well, it took mine 4 weeks. You do seem to have a good line but complaint is a bit of a harsh word. It's NOT like ADSL2+ where the ISPs can request interleaving on or off and as far as I am aware, manual over-rides to the DLM are very few and far between.
Cheers - N