My setup is a simple apple home sharing network.
I have a mac mini running OS X 10.6.8 and itunes 11.0.3(42) it hosts a lot of music, DVD's that have been re-encoded and paid for content from itunes.
The mac mini is conntected to the network over a very good gigbit lan and has 4 apple TV3 (latest gen) hanging off the network, and multiple PC/Mac/ipod/ipad devices hanging off the network.
All these devices connect using home sharing and work very well (I can use all 4 apple TV devices at once streaming 1080p media with no lag / delay problems)
There is one exception to this, my PC and Mac.
I have a Macbook pro running OX 10.6.8 and itunes 11.0.3(42) and a PC running Windows 7 64bit with Itunes 11.0.3(42). Both are also connected via gigabit lan, both run of SSD's so have excellent local disk performance, both have over 6 GB of ram at least.
If I open itunes and connect to the itunes home media server and play music, tv shows films all is well, ranging anything from a DVD rip to a HD bluray rip. as soon as I try to play a HD movie or TV show downloaded from itunes there is a problem. I get approx 30 seconds into the content and then it just stops as if I'd hit pause and never actually starts playing.
At first I thought this was buffering problems/flooding on my lan, so I isolated this, even though my network monitor shows lots of capacity on the lan, I removed all devices apart from the mac mini serving the home media and either the PC or the Mac, I hit the same problem.
To diagnose this further I opened a network monitor application on the PC, the playback mac and the media server mac mini and tried to open a file in itunes.
on the client and the server the network spikes straight away, and uses 100 network for around 5 seconds (if I do this with other devices such as apple TV's plugged into the network too the overall usage is lower, it basically uses as much as is availble, so %100 utilization isn't a problem) and then the network traffic just stops on both devices. The same is true of the disk activity, I see a raise is disk I/O on the home media mac mini for 4 - 5 seconds and then a lesser spike on the local playback machine both stop after 4 - 5 seconds in sync with the network stopping.
Both machines remain on the network fine, but the transmission of the media between itunes server and client just stops. I then open another file, a bluray rip, some music etc, and it plays works fine, return back to the paid for itunes content, it fails at exactly the same spot.
This happens on any itunes paid for HD movie or TV shows, so it's not just one file, it's approx any of the 200 itunes downloaded HD files I have on this machine.
I can play the files fine with apple TV's, I've tried watching 4 different apple downloaded itunes HD films at once on 4 apple TV's it works fine, it's only if I open the file via itunes with the PC or Mac.
All are linked with the same home sharing account so it's not / shouldn't be a DRM style issue.
Why is this happening on the more powerful PC/Mac computers, but not on the lesser apple TV, ipad, iphone devices ?
