No it certainly isn't normal to have two master sockets. Sounds like his DIY skills have got the better of him. Two main problems - first is the fact that until the t/p wire gets inside your house it belongs to BT and shouldn't be played with. Second is the fact that external junction boxes are prone to break down because they are not properly weatherproofed. It might cost a few bob but I think you need BT to have a look at the setup.
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Do you know that we're all in line for succession to the throne? Really?
Well, if forty-eight million, two hundred thousand, seven hundred and one people died I'd be Queen.