In the students home where I lived, a bar was openened yesterday and I had to put some professional audio equipment there which I lend from a good friend of mine. It was a very big success and my first time I was the DJ, but people sung and danced 8-)
Because the whole equipment, means the amp rack, 2 top speakers and one huge subwoofer of exactly the size of an ground loop. I assume my computers power supply unit is responsible for that (its been actually 20 Euros, which was really cheap for 420 Watts some years ago).
Today I luckily found a very nice solution around this issue: My work laptop does not produce a ground loop, so it is predestinated for a PC to amplifier rack connection. On my main PC I use foobar2000 (there is no good linux alternative and sadly, I'm on windows again for some reason). So I found edcast which is capable of streaming to Shoutcast and IceCast from foobar(it's actually a DSP plugin). Because I hate Winamp and Icecast is OSS, I used the latter. Now it nicely streams my foobar playlists to the VLC media player of the laptop. Theres a control delay of about 5 seconds, but regarding the point that the audio gets ogg encoded and VLC buffers 1200 ms, I'm really fine with that.
Now the whole students home has to listen to the music I like, it is very loud in my room now. I even changed my IM status message to "Students home now listening to [track] by [artist]"...