I then checked to Auckland and it showed only around 2000KBps which is strange because I almost always get 4200KBps, I also noticed that speedtest.net showed my location as being in Dunedin when every other time I have done the test it has showed the correct location (Warkworth, about 60km north of Auckland).
Since then all browsing, even to local sites has been very slow with youtube being practically unusable all through today and most other sites loading very slowly speed. I have just looked at my router's (D-link 504T) status page and it shows a total of 487 overruns with receiving and 8 Rx total error counts, what do these mean? I recall that every other time I have seen them they have both been at 0.
My ping to Auckland has also increased by about 30ms. Has anyone else experienced a similar problem. If so, how do I fix it?
[Edit] My location now seems to be detected as Warkworth again and national speeds are back to normal. Must have been a temporary glitch. ping is also back to normal.