Nothing at all special about the machine--completely stock base 21" model. Took it home, migrated data from old iMac via Firewire. Everything good for about a week. Now have had a few episodes where the machine (seemingly) won't awake from sleep state, regardless of mouse use, key presses, expletives, threats, bribes, and offers of arbitration. Have had to power down with ten-second power button press, then restart. All seems okay after that, until it happens the next time. Note, however, that this problem does NOT occur with each episode of the machine going to sleep. (Or trying to; whichever.)
In reading through a fair number of the posts above, I'd like to offer a few comments, ideas, what have you.
Firstly, it's almost certainly NOT related to variable power supply issues. Forum participants report it happening with surge protection, without, and with UPS. Possible, I suppose, that Apple procured a large batch of faulty power supplies, and the problem is intrinsic to those, but that explanation fails to account for why the problem has been present off/on for quite some time, with various types of machines. (At least one forum member reports it happening with a MBP, though certainly the preponderance (at least) seem to be iMacs of relatively recent vintage--though not all even with the last year or so.
Other hardware issues as possibilities are limited by those factors that are common to all of us having problems. This is where setups like mine may help reduce the list of suspects--all that we have attached to our machine is a power cable. No other USB devices, no printer, nothing. We do have an Airport Extreme network setup--have had for quite some time, and it has had no recent changes. The power cable is plugged into a surge protector, but see above re: that.
Already, we're starting to look at a software glitch as the likely culprit. Details of setups are going to be important here, as the problem could perhaps be related to interactions of screen saver and sleep, specific settings for each or either, perhaps even how any changes were made. How many of us made changes to the factory default settings of sleep mode for either display or machine? I've made a slight change regarding timing of things, but nothing else. One discouraging bit about the possibility of software glitch is that OS X reinstall doesn't (at least reliably) fix the problem.
But there are lots of possibilities in that arena (the software glitch arena--it's a big one--they featured it in a Russell Crowe movie a while back). Could it have to do with what program(s) are still running when the machine goes to sleep? I, for instance, occasionally leave Firefox running, and Mail sometimes. My wife likes Safari, but I happen to know it was NOT running during the last "won't wake" event for us. Not sure about Firefox, others, for us.
And how about software installation? Is it possible that there's an installation/setup step for something that, when done "just wrong", results in this? Are all the sufferers people who moved from old Macs and migrated data/settings? Could that be related?
If anyone has solved this--not found a work-around, but rather solved it, it'd be great to hear about it. I'm not looking forward to spending hours with support people trying to work this out.
