Seems to be an almost daily occurance now and my ping has gone up to 60ms from the usual 7ms, speed down to 94 down 7 up and the speed drop and ping increase always happens alongside the peak in the graph so VM must have a serious issue somewhere. It's not just the graphs that show the issue as pretty much everything slows down including general web browsing.
Edit: speed down to 55 down 6 up with 72ms ping now.