cliche

I've recently "switched" to a mac, and have some queries about audio with fast user switching. My girlfriend and I both use the computer, and share a Skype account (using SkypeIn so overseas friends and family can easily contact us). The way I've tried to set it up is 3 accounts: one for each of us, and a third to run Skype. This saves running two copies of the application, and also prevents voicemail fragmentation (it downloads voicemails to whichever user is logged in at the time).

However, and this is my main question: How do I let sounds from the "Skype" user play whilst another user is logged in and using the system? Skype isn't the only app. affected - if I play music in iTunes it stops when I switch users (though the song continues to advance, suggesting it's trying to play but the sound isn't being output to the speakers).

Any ideas?

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I can't understand why people are frightened of new ideas. I'm frightened of the old ones. -- John Cage (1912 - 1992)