I sold my R10 and the guy who bought it said it will not hold air. I bled the bottle down for shipping, but left a couple hundred pounds in it to help protect the seals. I had read in the past that a PCP would develop leaks if fully depressurized for shipping. He says " It won't take any charge at all. Leaks from the side of the bottle, and from the fill port." Anyone have similar experience? Will changing the o-rings solve the problem, or is is something more sinister?