Apple fixed the AirPlay bug and Hotspot bug for iTunes 11 users. A guide shows how to convert video on Mac for iTunes 11.
After iTunes 11.0.1 launched, lots of customers have many complains. Updating to iTunes 11.x, content streamed to an Apple TV (or other AirPlay device) can stop playing unexpectedly. This can occur as early as the middle of the first played song or as late as an hour or more into a playlist or movie. This is the AirPlay bug.
A usually successful work-around is to go to iTunes’ AirPlay menu and shift to the Multiple, rather than Single, option (see figure below). If your AirPlay device connects via Ethernet, another potential work-around is to switch from the wired connection to a wireless one. This is reminiscent of a similar switch that remedied an inability to install the Apple TV 5.1.1 update.
The next bug is the Hotspot problem. The symptom is a failure of the USB Hotspot option, when connecting an iPhone or iPad to a Mac. The most frequently recommended work-around is to use Kext Utility to replace the currently installed AppleUSBEthernetHost.kext file (located in /System/Library/Extensions) with a prior version as obtained from the web.
The tip of iTunes for you:
The next time you update iTunes and/or OS X, the replacement file may get wiped out by the newer install, with the symptom returning. Second, any custom modification to the content of the Extensions folder is risky. Older replacement files may turn out to be incompatible with other aspects of the current OS, resulting in unpredictable problems separate from whatever you are trying to fix.
Related: Convert video Mac for iTunes 11 Guide on