[davlefler]

It comes from one speaker then the other at irregular times but quite frequently. Noise comes from internal speaker if no externals are plugged in. This happens regardless of OS version. Thanks for the help.

[wlonh]

this used to happen to me with my rev2 beigeG3 minitower... i figured out what caused it:
a bad 'system sound' that i had chosen as my clock chime (set to chime every hour on the hour, only)... this sound was corrupted in some way and when i replaced it with another, completely different sound, all was well.

no more wierd pops and stuff. strange but true!

I noticed the problem was happening when my cell phone (or my neighbors) was somehow communicating with the cell towers. It happens regularly throughout the day, if my cell phone is nearby. It may be a possibility...