iTunes performance / sound choppy

[rschmied]

Hi,

I'm running iTunes 9.02 on XP SP3 in a VM on VBox 3.1.2. The host is running Ubuntu Karmic 64 on an Atom 330 Dual Core 1600MhZ CPU w/ 4 GB of memory. The virtual machine has 512 MB of RAM. iTunes should stream the (non-DRM) music from its library (alternatively streaming Internet radio) to an AppleTV (so no local sound output required). However, the performance really sucks. Even thought the CPU is not pegged (seen using TaskManager) and there's enough free memory, the sound output on the AppleTV (and local as well, if turned on) is really choppy.

Is this a general experience? Anything that can be tuned to optimize this? So far I have stripped down the Windows install and de-activated all unnecessary services, even disabled the anti virus scanner but it did not help. I'm clueless how to improve this...

The platform itself should have enough horsepower to do this task, IMHO especially since it should only stream content to and from the network.

Any advice greatly appreciated!
Thanks

[vbox4me2]

Minimize itunes.

[rschmied]

Unfortunately, that doesn't cut it. The very same stream (internet radio) plays fine from within VLC but is extremely choppy and repeating (like echo) w/ iTunes. This happens while using the virtual sound card (playing through host sound card) or while playing the audio via RDP on the local computer. As it works OK with VLC I can most definitely rule out a network performance issue. The CPU should be OK as well, as decoding that stream with VLC pretty much leaves the CPU at ~70-80% idle. Is this a general problem with iTunes?

My goal is to play a music library via AirTunes (e.g. streaming it to another device and have it play from there to my home entertainment system). But even this is not working well. Is iTunes such a resource hog or are there knobs that can be turned to optimize the setup?

[treasuregetter]

Were you ever able to solve this problem? I am experiencing an almost identical issue. In my case I am streaming music from iTunes to Apple Airport Express (Airtunes) units. I get skipping and hesitation all the time and can't seem to resolve it. Like you, I am also running Windows XP Pro as a VM via Virtualbox On OpenIndiana (OpenSolaris distro). Everything else works fine. All my other VM's have awesome speed over the network, including linux vm's, xp vm's and windows server. Also, I had the same problem when i used Windows XP 32 and 64 as the host operating system for VirtualBox. Do I need to modify a TCP stack or is there a way to enable QoS on Windows/Virtualbox/OpenSolaris? Any help would be greatly appreciated!

[vhkristof]

Is there a solution for this ?
I'm also struggling with this issue.

My specs should suffice (Dual core 2.6 GHz, 4 GB ram)

[Aborro]

If anyone is still struggling with this issue...

I had the same problem running iTunes on a Windows XP guest. I am now running Windows 7 as a guest OS with the latest iTunes Version 10.1.2 and streaming to my Airport Express clients is smooth and hiccup-free.