My Core Solo Mini is refusing to sleep. When I put it to sleep, it keeps humming for a couple seconds, and then wakes back up again. I've tried ejecting all of the disks and images (except the internal hard drive) to no avail. Any ideas?
What apps are you running and what peripherals do you have plugged in? Try disconnecting them one-by-one to see if you can find the culprit.
I tried disconnecting all of the peripherals, but it still has the same problem. Right now, I'm running Firefox and iTunes. The only background programs I know about is Growl. I disabled wake-on LAN, and I do not have any Bluetooth devices paired with my Mini.
Reset the smc: http://docs.info.apple.com/article.html?artnum=303446 follow the instructions exactly.