Trouble with iTunes streaming dropping out on MacMini

I have both a spic-and-spam brand new 2,3 Ghz MacMini with Lion, and a wind-up steam-powered PowerBook G4 running 10.5.

Now: The PB runs a nifty little app called "Audion 3" that streams any MP3-stream nicely to me. Trouble is, it’s PPC and no longer supported. Thus I’ve had to resort to iTunes on the Mini for my favourite radio channel, the Norwegian State Broadcasting Company’s "Always Classical" stream (which, of course, is not listed in the default radio staion list in iTunes, and, the NRK, as it is known in Norwegian, is not at all Mac-friendly, their on-linme radio/TV does not work especially well unless you resort to various badly supported plug-ins).
When I run this stream in iTunes on the Mini, iTunes stops all the time to "rebuffer" the stream, something I find rather strange, as the box ought to have enough memory out of the box for such an insignifcant task. Second, the tiny app onj my waaayyy slower PB runs just fine without any such silliness. And, they are on the same Airport, on the same line (ADSL).
I have been looking hard for alternatives to iTunes, but they all want to lock you to some noise-channel or noise-streaming serrvice, or (and) they want to be bells-and-whistles "media centres", which I am not looking for.
The URL is http://lyd.nrk.no/nrk_radio_klassisk_mp3_h
for those who want to try. I did finally find an alarm clock app for iTunes (since Apple has not bothered to include sleep timer or alarm clock into it, but has instead focused on a lot of stuff I have no use for), but it has limited value since iTunes keep losing the stream for "rebuffering" all the time.
It is quite annoying that a new Mac cannot do what an ancient coal fired Mac can do.
Does anybody have any suggestions as to what part of the Mini to whack with something hard?
Thanks/