Just for grins, is it OK to have NOTHING plugged into the USB port? The let the Mac go to sleep... so if THAT works, then we know it is not the Mac, but something else. Then add one of the USB devices... let the machine go to sleep... wake it up, disconnect that peripheral and add something else... Do this through each item... Then, have two items... then add a third and disconnect it... and so on untill everything is plugged back in.
I know it sounds tedious, but the best way to troubleshoot is to start at one "end" and work slowly to the other end. Starting in the middle can get confusing and lead to false assumptions.
Also, does the LaCie drive ever sleep? If not, its staying awake *might* be keeping the Mac awake... Have you asked La Cie - or checked their support area? I realize you have powered the LaCie off - which leads me to believe it is not that peripheral - or perhaps its interaction with another item on the USB buss.
I *think* the "Not wake on network activity" is associated only with the ethernet port... not USB.
I have been having trouble keeping my Mac asleep.
It won't go into sleep mode by itself. When I manually put it to sleep all seems to go normally (i.e. eventualy the screen goes blank and the power light starts to pulse), but seconds later it wakes up.
I think I have narrowed the problem down to my external LaCie 250GB harddrive. If I disconnect it from the USB port on the back of the computer 8 out of 10 times the computer will sleep. I have tried simply turning the LaCie drives power off, but that doesn't seem to help.
I have the computer set to NOT wake on network activity.
Any ideas?
20" iMac G5 1.8GHz
1GB RAM
External 250GB HD (USB 2.0)
Airport Network
Mac OSX 10.4.8
15MB Verizon FIOS Broadband Connection
Belkin USB Hub
Epson RX700 (connected to hub)
iPod Dock (connected to hub)
Iomega External DVD Burner (connected to hub)

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