27" iMac only wakes from sleep on second attempt

[maccauni]

My base 27" iMac, as the title suggest only wakes from sleep on the second attempt. If I wake the mac in the usual way(magic mouse, keyboard or power button), I hear the hard drive start but the screen stays blank. If i then press the power button it will put the mac back into sleep then if i then wake it up again everything comes on fine. This only seems to happen if the mac has been sleeping for longer than a few minutes, but it does happen every single time.

I've obviously checked that the bluetooth devices are allowed to wake the machine. Ive been looking through various forums and haven't come across anyone with the same problem as me so far.

Ive already tried resetting the smc,pram etc to no avail.

On the plus side im not getting any of the flash problems.

Any ideas on what could be the problem?

Thanks

 

[rspencer86]

I have the same problem. If the iMac has been in sleep mode for any significant amount of time, clicking my mouse or pressing a button on the keyboard does not wake the display (everything else does come back on, just can't see the screen).

I've tried to get into the habit of pressing the power button to wake from sleep as it seems to work the best, but even this method sometimes leaves me with a blank display.

Apple needs to get all of these issues (flickering, flash video, etc.) ironed out ASAP.

 

[MucMike]

Mine too...

Plus this nice little blue feature: