Okay, hopefully I can describe this in a way that makes sense. I purchased a new iMac 5k 27'. iTunes library streams just fine and I have no issues, that's until the iMac goes to sleep. If I try to open my library via the Apple TV while the iMac is asleep, it'll keep searching for the library with no luck. It's only after I wake the iMac and try playing something in iTunes (music/video) that it works again. My library is all on an external drive connected to USB 3.0. In the power options I have everything checked that I should. Wake for network access, don't put the drives to sleep, etc. Never had any issues with my mac mini but I never let that little sucker go to sleep. Suggestions? THANKS!