Try replacing the air in the container by using compressed air from one of those cans of duster, for blowing out keyboards. It's not just air and seems to help, I don't know if it CO2 or what. What I do is stick the tube in the can with the lid cracked a little and let it blow in for a few seconds, pending on the size of the can that has the (bad) air. Hope this makes sense.
CarverJerry
ver. 1.188 Win 7- 64b with 6 GB ram @ 2.8Ghz and dual 1Tb hard drives. Rock Chuck & Ringneck vacuum system hooked up to a Harbor Freight large vacuum. Center line text, conforming vectors.