ok, my first suggestion would be to remove IE... it's an outdated browser anyway, others such as Firefox and Chrome will offer a significantly better experience...
secondly, are you running sound from onboard your motherboard, or a seperate sound card?
If it's the latter, i'd recommend removing all drivers for the sound card, and redownloading from the manufacturers website.
It is a possibility that simple 'wear and tear' have occurred, and components within the computer itself, like the soundcard or motherboard, simply need to be replaced... if this is the issue, then i would recommend moving to an entire new system instead of simply updating the outdated parts.
This sounds logical. (Gee, now I sound like Spock
) However, I never understood everyone's hatred of IE. I have never really had any problems with that browser since day one. Even though Firefox is my main browser