constant dinging, problem scrolling

Hi,
My Mac keeps making a repretitive dinging sound (not the sound you get from an email, but more like an "error" ding), and I have trouble with scrolling in drop-down menus. I thought it was the mouse, but the sound remained when I unplugged the mouse. It will be like this for hours, then stop briefly, then start up again for no apparent reason.

Has anyone else had this? How can I correct it? HELP!

My system is OS 10.4.11. Thank you!

Desktop or laptop?

constant dinging

Hi,
It's a G5 desktop. I tried resetting the PRAM but that did not solve the problem.

think im getting the same problem im on 10.6 2.0ghz aluminium macbook

unplug your keyboard and restart. if you have another I'd try it. Stuck key would cause dinging.

How consistent is the dinging? every second? every minute?