Does dust affect audio equipment, if it gets in through the ventilation slits? TIA.
Yes it makes it dusty. yecchh! No actually it will affect the cooling of the compnents within. I blow mine out at least once a year and it gives me the opportunity to clean the connections.
Sure it does. It covers the internal components making them heat up more and can cause them to fail prematurely. Dust can also cause noise in a system.
A fan or a vacume cleaner affects sound even more than dust when both work together in a small listening room he..he..
With very high voltage power supplies, such as required for a CRT (TV picture tube) dust will be attracted to, and will eventually cause failure of the power supplies. For low voltages, such as used for solid state equipment, there is little tendancy to attract dust. Also, with the low operating voltages and higher circuit currents, the effect of a little dust is minimal. Mechanical items such at disc or tape transports benefit from occasional cleaning, and, probably more important, lubrication.

But, you may enjoy an occasional visit with those expensive capacitors, and, like chicken soup, can't hurt.
Thanks for all the responses,

Since prevention would be ahead of the game (? better) would covering the components, or placing a Plexiglass "case" around the rack between listening sessions be better? My area isn't any more or less dusty than I'm sure is average, but I'd like to minimize/prevent all dust. Thanks.
It all depends on wether or not you leave your equipment on all the time and how hot things get. The heat trapped by a plexi-glass cover will be more damaging than some dust.
My house was dust central until I bought an electronic air cleaner for the furnace. It may be somewhat expensive but in my case it was well worth the money. Goodluck.
"Since prevention would be ahead of the game"
I would recommend showering more since most dust comes from ..... us. =:-)