Originally Posted by
TURIN
According to the BT chap that came round, that is the cause. Something to do with separate circuits.
I asked a question some time ago about using these plugs to extend my Internet to a shed at the bottom my garden. I was advised not to bother.
Again, this is nonsense. You cannot connect powerline adapters across different phases, but you can connect them across different circuits within the same phase supply. They will work across any circuits on your side of your meter. The connection may be poor because of old wiring, but that's a different question. BT engineers aren't electricians, and are quite happy to trot out old wives' tails as received wisdom (aka bull!!!!).