[auburnham]

Thanks for everyone's feedback. I went through all running processes one-by-one, killing, then trying to sleep. The phone finally slept after killing "Media Storage". This may be related to another issue: No music is showing up in the Music app, though Media Scanner is running. There are no ".nomedia" files in any of my folders.
Now that the phone sleeps, I'll start investigating the music files. Thanks again for everyone's help.

Shawn