Sounds like either a failed box, or a software drop has gone wrong. Either way...
I wish there were a better answer other than to try calling again. There's a text message service (07533 051809) which normally responds after a day or so, or VM forum staff do pick up posts here, but their current backlog is around a week.
As a long shot, you could try swapping the boxes around just to prove the problem, but I don't realistically see it helping.
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