Does sweat affect earbuds?

Well i like to use my iPod when i workout. I gotta ride my bike to the gym, and then i work out. So, naturally, i work up a nice sweat. Well i don't use the iPod buds, because they dont stay in tight enough. I use some Sony around the ear ones. I go about 3 times a week and thats all i use them for. But now the left bud doesnt work. So my question is, does too much sweat affect the buds? Does anyone know if like something covers it? Thanks in advance.