Just spent 2 weeks in Cocos, great sailing, hot as heck, none of the North Kites (2007/8/10/and 2011 models) there had this issue..... that I'm aware of ......and my 2010 12m + 9m Rebels were and are just fine......
So it looks like its a sporadic thing that will be a pain in the butt if it happens and we have alerted the manufacturers to this issue pretty clearly in this forum...... hopefully they understand and will deal with it
(I live in hope as no manufacturer needs/wants these issues surely)
Be interesting to note if this is an issue in other hot climates...Brazil eg...??
Or is it just certain batches of bladders/valves.
Being cooler over here in NZ is sometimes a good thing!