I lived in Hawaii in a house on a hill where strong winds carried air laden with both moisture and salt (coconut trees would die from salt damage). Any equipment left outdoors would be subject to accelerated corrosion. But, indoors, corrosion was not that big a problem. The salt settles out of the air pretty readily if it is not moving very vigorously. To be extra safe, I would keep the gear away from direct exposure to a breeze from the outside, and perhaps, a cabinet would help too.
As for humidity, it is hard to say how much it would affect the life of your gear and your CD's. I suppose certain kinds of gear are more sensitive than others. For example, I know that Martin Logan electrostatics are somewhat prone to failure from the wires leading to either stator or the diaphragm corroding in high humidity environments (a friend's speaker failed this way after a little more than a year of storage in his garage in the Washington DC area (a VERY high humidity environment)).
As for humidity, it is hard to say how much it would affect the life of your gear and your CD's. I suppose certain kinds of gear are more sensitive than others. For example, I know that Martin Logan electrostatics are somewhat prone to failure from the wires leading to either stator or the diaphragm corroding in high humidity environments (a friend's speaker failed this way after a little more than a year of storage in his garage in the Washington DC area (a VERY high humidity environment)).