The other day I stopped receiving sound from my external speakers that are connected to my computer (G5 PPC 10.4.11). I only changed one thing yesterday. I unplugged the external speakers from a power bar and plugged it into a wall outlet. That's it. And now there's no sound from the external speakers. So I plugged the speaker's power cord back into the power bar the way it was before, but there is still no sound. The input level in the Sound window "visually" illustrates an audio signal when connected to the soundflower (2ch) input. After going through Apple's diagnostic checks for no system sound, I have found that my external speakers are not specifically listed in System Profiler. Under Audio (built in) there are two options listed but nothing about the external speakers. The external speakers are a basic plug and play device. I have refreshed the System Profiler window but the refresh still doesn't acknowledge the presence of the external speakers. I've also looked at more basic things like making sure the mute button is not checked in the Sound window, and ensuring that the external speakers are connected to the computer. Maybe my focus should be on trying to get the System Profiler to acknowledge the external speakers. From what I can tell, the System Profiler automatically registers a new device when it gets connected to the computer. Thanks for any tips on how I might restore sound to the external speakers.