Ipe:
There should be a red standby led when you plug the unit in.
The powerlink has a 5v trigger which comes from the Beocenters and tells the speaker to turn on at which point the led changes color to green. So for it to play you need to send an audio signal as well as the 5V trigger.
But if you are getting absolutely nothing… start with the power supply. Maybe a fuse?
Is the cord plugged all the way in? The receptacle is in a very awkward location and its not always easy to plug the cord in properly.
Derek