I noticed that as well yesterday during my run. About a mile and half into it, the sound faded to the point that I could barely hear it and for the rest of the run, it kind of just came and went.

When I got home, I realized that the back of the unit (near the speaker) was completely drenched with sweat, so like you said, I assume that has something to do with it.

I wiped it off as best I could and today it sounds fine, but I hope to god this doesn't become a bigger issue - My Garmin is my lifeblood!

Anybody else have similar experiecines or additional insight?

would wearing one of those terry wristbands I see at modell's guard against this? I'm currently looking into buying a 305 and this would be a dealbreaker I think...