Just to add that this has been going on for several days without interruption. I'm always at 40mb maxed out even in the middle of the night.
Trying to get help from Virgin by phone but the poor chap is just reading a script and can only offer an engineer in 5 days. They say nothing can be done from their end to check the line or provisioning.
Meanwhile we have constant dropouts and cannot use Citrix or VOIP.
Any ideas of how to proceed, or anything I can try in terms of the cables/splitter or router to rectify it?
Nope - nothing you can do because the problem is downstream power levels are far too low, that will need a technician. I'll flag this for the forum staff who can book you a technician if that's needed (the alternative is a known area problem being worked on already), so you won't need to endure the telephone contact, but it is pot luck whether they can get a technician slot any earlier.
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