Hmm, i found something else on
messenger site concerning Intel network cards:
If you are using Windows XP and you have an Intel network card, you may experience problems using the MSN Messenger audio feature. Some Intel network cards enable 802.1p wireless connection support by default, but don't provide a way to disable that support.
Turning off the QoS Packet Scheduler may fix this problem. To do this:
In Windows, click Start, and then click Control Panel.
Click Network and Internet Connection, and then click Network Connections.
Right-click the network or Internet connection that is currently enabled, and then click Properties.
Clear the QoS Packet Scheduler check box.
Restart your computer.
Sign in to MSN Messenger and try using the audio feature again.
If that's not working please specify wich OS you are using etc. I'm afraid it can't be solved if you are using wireless.
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