Latest (and last) update:
After a transient power outage (unrelated to Broadband) the Hub powered back up, but both DVAs went blank (neither was on the circuit that flipped) and wouldn't come back. After a while of deadness, I moved them to next the Hub, and eventually (multiple unplug replugs) their lights came on and they reconnected. Moving them back to their proper positions, both went back to being dead. Hours later, they re-established contact. Meantime, phoned EE yesterday and they detected the Hub didn't reach minimum speed as contracted, thought that was the cause of the DVA issue, and ordered an engineer to come out and test both problems: blank DVA and slow speed.
He arrived this morning. Re slow speed, he simply didn't accept that we had only a Junction Box and no Master Socket. I well remember three Extension Sockets being installed about 40 years ago so we could move the phone (hard-wired into the Junction Box) away from beside the Junction Box in the hall by the front door (these were the days before cordless phones - even the ones with the big long aerials). I well remember asking BT to provide a Master Socket in place of the Junction Box and they flatly declined (even at a price) because it wasn't broken. So don't tell me I have a Master Socket.
The upshot is that the engineer installed an Openreach Master Socket in place on the Extension Socket that feeds the Hub. It's ten or twenty feet away from the Junction Box and I have no idea of the wire's route which has to involve going under the bathroom and the airing cupbaord. The engineer explicitly ('cos I asked him) accepted that Openreach/BT was now responsible for everything up to and including the Master Socket. The Hub speed was improved somewhat but still not up to standard, but I don't mind because I'm not a heavy user.
Re DVAs. The one downstairs failed in front of his very eyes. Blank. The mains socket is faulty - let's use the next one - it worked. I insisted he unplug and replug the DVA: it failed. So, two sockets duff? He came upstairs with a new DVA and plugged it in near the router - it failed. So, three sockets duff? So, he plugged it into the extension lead nearby - still duff. So, four sockets duff? No, he had forgotten to switch it on at the wall. And then it worked - and continued working in both of the so-called duff sockets downstairs.
Apart from "I've never seen these things just go blank before" - well, he has now - he had two messages for me: these DVAs are rubbish and you'll be going FTTP "by the end of the year" so all this will be obsoleted. No - the DVA problem will remain if it's them wot's duff. "by end of the year" - also no, Openreach says "it's 2027". I don't want it and I don't need it and I can't see anyone with any nous thinking carefully and sensitively about where and even how to plunk boxes on my walls/cladding inside and out.
So, the duff DVA issue remains. The engineer's analysis of what issues there were was poor and his fix more suck-it-and-see, especially having sucked it he saw the DVA blank. But I've got a Master Socket for free. I have a DVA-avoidance workaround in mind - but I will in practice lose the answerphone function. Once upon a time, phones were simple and reliable, now modern technology has crushed the life out of them.
