BEST PRODUCT SINCE SLICED BREAD, WORST DEFECT SINCE TOYOTA CAR MAT...Ok maybe this one won't kill you, but it sure will kill a workout.
Same thing as the rest of the posts...exercised for ~20min, shuffle becomes inoperable (no volume control) then shuts-down and will not start again. Waited a day, used restore function in iTunes, had to reload song list to iPod.
Tried something similar to the wrapping it with electrical tape solution but instead of electrical tape i used plastic wrap with a little tape at each end to keep the moisture out, it did not work.
FRUSTRATED AND INFURIATED, wish i had purchased a used 1g Shuffle at least you can control the music, sound and it works.