Won't wake from sleep for schedule

The computer goes into sleep (S3), hybrid sleep (S3+4), and hibernation (S4) properly. Wakes on mouse, keyboard and network from all three of the above states. But won't wake on schedule from any of the above states! The computer is a desktop with two Ceton InfiniTV-4 cable-card tuners hosting Windows Media Center and trying to wake for TV recordings. It has two 1TB mirrored and eight 2TB...