I have quite a collection of scotches, and like to have a diverse selection open to cater to the likes of my mates. As such, I may have 6-8 bottles open at any time. However, on average almost 2 out of three bottles that have been open more than a couple months or so develop deteriorated corks; they just twist off or crumble when I try to open them - enormously frustrating! It's not because they are too dry, since I live in Houston, and they stay upright in a failry dark place. Could it be from too much humidity? Or temperature swings (the house often will go to low 80's (F) during the day, and then cool off (74-76F) when we get home in the evening and overnight). I've thought of "waxing" the necks and tops of the bottles to protect them from the environment, but that does not seem to be very practical except for an ocasional one-off for special bottles. Any good advice appreciated!