white noise on performa 6400/180 speakers

My Performa 6400/180 has white noise coming from the internal and external speakers.  The noise also comes out of the front headphone jack.  I can turn off the noise by turning the internal speaker down and by putting a speaker wire into the back speaker out port (but only without speakers attached to the wire).  Turning the system volume down does not get rid of the noise.  The noise turns into a slightly higher pitch when I click on a menu button.  This noise used to occur only after long cumputer usage-6 hrs, but now it's there right after bootup.  PLEASE HELP!
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

seanorAuthor Commented:
Adjusted points to 150
Although you didn't say what level this noise is, I assume it's higher than normal. Since it seems to be getting worse, it sounds like the sound chip is going bad. Could also be a pwr supply issue but neither of these would be simple fixes. One last idea -- if the inside of the computer has lots of dust or is very dirty, you might try blowing it out or using a freon based "spray wash."

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Apple OS

From novice to tech pro — start learning today.