This only happens during weekends, during peak daytime hours, i.e. 11am-11pm roughly. Where I usually have 20ms in Steam's server browser, almost every server increases by up to 100ms. Speedtests seem to be completely unaltered from times when this is affecting me to when it isn't. I get around 36Mb down and 1.5 up no matter what. It began last weekend or the one before that.
My server browser. It isn't too bad right now, but notice how the UK server highlighted is ~70ms whereas it is usually in the low 20s.
Here is a trace route to that UK server. It seems to get stopped at 188.8.131.52. Here is another tracert to a server in the Netherlands on which I usually have 30ms.
This is the view of net_graph in Team Fortress which tracks your ping and packets lost. Notice the 1000ms spikes and just how [censored] unstable it is. In the past it has been a horizontal line right at the bottom of the graph.
This is my exchange.
Thanks for any help you can give.
Edited by ltadsl (Sun 29-Apr-12 19:23:52)