IPv6-problemet?
Fra macfixit:
"AirTunes streaming broken? Store issues? Enable IPv6 If you are having problems streaming to an AirPort Express base station using the AirTunes function under iTunes 7.0, or having problems accessing the iTunes store, make sure you have IPv6 turned on. In order to change this setting, open System Preferences and click on your currently used interface (Ethernet, AirPort, etc.). Click on the TCP/IP settings for the interface -- at the bottom, you should see a button which says 'Configure IPv6...' click it and make the setting "On." Press the Apply Now button. As we previously noted, however, having IPv6 turned on may result in varied network slowness. Another possible solution for video playback issues In our early morning update (see the "Video playback issues" section below) we noted that some users are reporting a loss of ability to playback various videos under iTunes 7.0. This includes video podcasts, home-encoded video and more.
It now appears that one potential solution to this problem involves removing the following file:
QuickTimeH264.component
from the folder /System/Library/QuickTime, then quitting and re-launching QuickTime.
MacFixIt reader Ben Donnelly is one reader who had success with this workaround:
"I found that by simply dragging the H264 Component to the desktop and allowing the system to re-create another one resolved all of my video issues. I'm now able to view videos successfully. I can only assume that the install of Quicktime 7.1.3 corrupts this plugin somehow.""