Hi, and welcome Andy.
Firstly, I can only comment on what you have said here, so apologies if it turns out to be anything otherwise.
It does indeed sound like you have a REIN issue from you description of severe errors, and constant LOS (Loss of service). To back that up, the engineer has done exactly what is required by a non-REIN trained engineer, by way of the work he has carried out. I can only assume he also got a good PQT Test (Pair Quality Test) with an AC Balance at least over -50dB, and hopefully over -60dB ?? Plus, each individual leg-resistance within 3ohms of each other, (IE:there are just the two wires from your premises to the Exchange, and they should be roughly equal in resistance).
Now we have got the metrics out of the way, what should have then happened is that the same engineer rings the REIN team (Now based in our DCoE - Diagnostic Centre of Excellence
), and they should have raised a REIN case. This is for us, you and the ISP to add and /or read the notes. Some REIN tasks can take 10 mins to resolve, some weeks and months. It depends on the time REIN affects circuits, and accessibility issues. The REIN case will be a 'Kept log' of any updates made by the engineers.
Additionally, the same team also raise a CSS task for the engineer to work to. This is just like a 'dummy job' that we can download onto our laptops, so that our management systems (i-POP) can still spy, sorry monitor, our whereabouts and our effectiveness and efficiency. The down-side ?? These tasks only carry 1 hour on them + travel time. It can take a good hour to collate info !!!
So, to answer your question about, "What do I do next ?" .......... the answer is not much, unless you wish to carry on doing a bit of your own detective work ?? This can be a great help to us when trying to locate REIN, but not a necessity. The key to locating the REIN is to turn the volume down as low as it can, but still able to detect the REIN.Then by driving around you should begin to pin-point the actual area the interference is strongest, if you haven't been nicked for curb-crawling in the meantime ??. After that, it's really a case of asking other individuals if they are being affected, and tuning a small AM/MW portable radio in to 612Khz and trying to further narrow down where the source is emanating from ??
I have never done as much REIN faulting as I have this last two weeks, and quite a few sources were actually PSU's that were the victim of lightning strikes. Satellite set-top boxes, Plasma TV's and Aerial boosters are a common cause, but the full list is exhaustive and alsways being added to. Such as these 'digi boxes' that are being bought from China/Taiwan via e-Bay, they are quite bad as well.
The only pro-active part you can play, is getting those near you who are also affected to raise a fault with their ISP, and to keep pushing your own ISP to in-turn push us to attend site.
As you may or may not be aware, REIN faulting is mainly a gratis service provided by us, as our network is passing to the standards set down. It is 'rogue interference' that is causing the problem, and we can't be held responsible for every piece of electrical equipment manufactured. Ergo, REIN faults
can take a back seat in the workstacks, as it is obviously more business-like to dish out work that we get paid for. But, i have noticed of late that even with our very high stacks, the REIN jobs are being sent out as well.
Hope this gives you a little more insight ?