Sorry to bother you all.

I unplugged the splitter (where 2 connectors are connected to 1) from the Mac Mini. At that very moment the music started playing, through the computer inner speaker.

That made me wonder... Did I connect the correct plugs in the splitter? After some investigation I found there were 3 connectors behind the cabinet. I must have plugged the wrong one in the splitter.

Now I remember my son sometimes goes on investigation. Maybe he had unplugged the 2 connectors. When I figured out there was no N.Radio, I plugged in both connectors, without knowing one of them was not correct.

So finally problem solved. 

I have a also a problem but after 30 minutes compeet silence. Restart the mac mini and I have sound.

The strange thing is it happens every time after about 30 minutes no sound. Everything else works fine.

Anyone got an idea?

Chucky, are you using Phil's Linkplayer in beta version? This SW is programmed to terminate after 60 (not 30) minutes, but you can optain a version from Phil that doesn't:

http://web.me.com/philrobin/LinkPlayer/Feedback.html

No I use BM-link. Put the Mac to sleep yesterday and again one song and after that silent???

I rebooted and works fine,,,,