I had a problem with the 2013 Cartels highback foam ripping off after 3 days on the mountain. Swapped them out for 2014s at my local shop and they've actually been fine.
My understanding is that Burton's warranty is awesome. I would give them a call and they'll fix you up. Hopefully just a fluke- they sell so many of these things that I think if there was a widespread problem we'd be hearing more about it.