This may be owing to my local UBR being 'oversubscribed' but I notice that running tests during the daytime gets speeds of very near 10MB (usually 9.5-9.8). I've tested it in the evening and it ranges between 1-2MB. I've tried both the speed test on here and
www.speedtest.net.
I'm just surfing the net normally, not doing any big downloads or anything at all. Is this likely to be the oversubscription or throttling of bandwidth (can't remember the name of it - where they reduce your speed)...?