There was some work done on the uBR about a month ago .. This appeared to cure my issue, for a week.. now ping fluctuations are back.. i havent tested for loss extensively though. The proxies appear to be misbehaving as usual, or it could just be the problem has returned since the work. The dns issues as of late haven't helped matters
I don't think pinging the uBR in my instance will prove anything, as the problem seems to lie between my house and the uBR. It's being handled way high up by NTL though, hopefully!