It's really frustrating indeed, especially because the modem is next to the TV, so I got to stare at that flashing ready light for days straight
I suspect the upstream could have something to do with it, as my upstream transmit power as taken at random intervals over about 10 minutes was 61-46-33-61-21-8 dBmV. I actually meant to write in the first post that the downstream signal was too strong, as I'm literally 10 yards from the box, but I would have hoped that the tech who tested and mounted the downstream attenuator could have checked that as well.
When the guy on the door today told me there was nothing he could do I said "I think there could be a problem with the upstream" and he said "as I said, I'm not the network guy".
No offense intended to the Virgin techs here, but my suspicion is that the motivation and work scheduling system is really off. Like there's X assignments, and once you've ticked those off you can go home for the day (my tech today shouldn't have arrived until 3 they told me, but came at 11.30). Or pay per incident, and as long as it works when you leave the house it's "ticked off". I've read that attenuation is very much about distance to the box, so I'm disappointed that the installing tech didn't check it.
How about checking _everything_ at the time of installation and mounting whatever dongles are needed to get upstream and downstream perfect? Surely it's a lot cheaper than having installed customers cancel. I don't agree with the attitude that "If it works, then any numbers are OK" - because obviously sometimes it STOPS working.