I can't reply to your latest message so I'll do it here. After asking again, I was told that pronouncing negative/positive with a V is not the standard form, and despite the fact that this form of pronunciation is prevalent in some (rich) areas of Copenhagen, it sounds pretentious and snobbish.
Again, this is just what I've been told and definitely doesn't come from any personal knowledge I have.
I asked a couple of native Danes, and there is a dialectal difference: people from Copenhagen tend to pronounce it the way it is in the recording; it's also how I pronounce it. Some people from Jutland (or maybe even Fyn, I don't know about this one though) will pronounce it the way the person you asked does.