Storm.3814

I go through periods of approx 1s ping at seemingly random times but I have noticed that they only happen when I am in the heart of the mists or an actual SPvP match. I tested it today. Ping spike started mid match - game was lost because I was basically a non-factor with 1000ms. I logged over to a character in LA and my ping almost immediately dropped to normal. Back to the heart of the mists - over 1000 again almost straight away. Is this a common issue? Anyone got any solutions?