I'm with Talktalk, don't laugh, they are not all bad it is their relationship with BTOpenreach and the service you get from BTOpenreach is a post code lottery.
This is a good day, if the sun comes out I get disconnects and eventually speeds as low as 150 Kb/s
Last year I had an all out attack on TT, managed to get a new NTE5 socket but it made no difference.
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I have a saying about BB in the UK, it is like running high speed trains on Victorian lines but then I think they could do things right in those days.
Bill.