If you're worried about earbuds, just get some standard headphones. Bulkier to carry around, but SO much more comfortable (or maybe I'm the only one who finds earbuds horribly uncomfortable.)
I doubt earbuds are damaging your hearing, but depending on how often you wear them, perhaps you're pushing wax into your ears and that's making things sound a little muffled. That's easily rectified - pour peroxide mixed with water (half and half) into your ears, hold for ten minutes (ignore the buzzing/popping of it when it bubbles; that's supposed to happen) then tilt your head to pour it out, and put in a couple of drops of rubbing alcohol to evaporate any leftover liquid. Repeat for the other ear. I do this all the time to make sure I'm not getting too much wax buildup (I see to make more earwax than the average person, because my ears always seem to be getting clogged.) It's also supposedly a good way to head off an impending headcold, but that's never worked for me.