I tried Mad Mick's suggestion of connecting via ethernet rather than wireless and it seemed to work OK so I'll leave it at that until we get a reply from BT. That is a bit defeatist though if that is the only way to do it. Makes a mockery of the idea of a wireless system.
I didn't want to make any alterations to the router itself at this stage in case it has to be returned/replaced.
Thanks again for the help and I keep you posted on what BT say.
Spent too much time on the phone this afternoon trying to sort out this problem including doing firmware updates and the MTU adjustments suggested by remind.
Nothing worked so the device is being returned.
Apparently this was a common problem with the previous model in this 2xxx series but they thought that was now overcome. Obviously not. Some suggested blame was also attached to the high speed of ADSLMax!!!!
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