Have a look at this Cisco document:
http://www.cisco.com/en/US/docs/cabl...k_caveats.html
This is more in the realms of the expertise held by BBings and xo, but for those of you wondering why VM can't fix their problems, look at this list of major software faults in the Cisco UBRs.
I don't know if this model of UBR is relevant to VM cable broadband - I suspect it is; but if these models are deployed with the listed IOS and the events concerned are occurring, many of the faults reported in the forums could be explained.
In that case, VM could simply be waiting on Cisco's fix.
This could be a red herring on my part - we'll soon know when this is pounced on!