Here's the email I got from Elgato today. It pretty much sums up what was happening with my computer. So maybe when this happens to some other unsuspecting fool, they'll find this entry via google and not be stuck scratching their head like I was.
A tip of the hat to Jeff, who called it. He was on the money when he said it was EyeTv. I have nothing against EyeTV at all. I think it's a great thing to have, and I'll probably use it again. The solution was simple, just a matter of fixing my preferences.
_____________________
Thank you for contacting Elgato Systems.
One reason the Mac may be starting up is related to your EyeTV Guide
preferences, if you have it set to automatically check for programs scheduled
via the TitanTV website (tvtv if you're in Europe or IceTV in Australia). There
is an option to wake the computer if necessary and this option can be disabled.
The file Wakein, located in Library/Application Support/EyeTV is responsible for
writing to the power manager on the Macintosh. Quit EyeTV, erase Wakein and a
new file will be created the next time you launch EyeTV.
There is a known issue with EyeTV Hybrids waking when plugged into USB hubs, but
I haven't heard of it with EyeTV 250 devices. We're working with Apple on a
solution.
Have you tried resetting the PMU/SMU? The PMU is a subsystem which controls low
energy and power related functions. You can find instructions for resetting your
PMU from apple's website: http://www.apple.com/support (the instructions vary
depending on which Mac you own). If you have certain G5 models, or an Intel mac,
then the computer has an SMU instead of PMU.
Regards,
Andrea Lindgren
Customer Support
Elgato Systems LLC
Posted by Zoso at July 27, 2007 05:34 PM