Recently my sound on my computer has been muffled with my headphones. It's muffled usually on websites..except myspace. It's watery sounding and muffled and low on media player. I know it's not my headphones because they are brand new. I thought it could be because sometimes i accidently rip my headphones from the headphone jack...and now the jack is slightly loose. But then that can't be it because last week the sound was perfect again..but now it's muffled, watery, and low again. What is it? And how can I fix it?