--> EDIT: I just connected the speakers to my Iphone and the problem is solved. It is not the speakers, it's my Mac.. so.. new problem. Thx anyways. 

 Hi, 

Half a year ago I bought the Beolab 4 speakers for Pc/Mac (so no link option). The line in mode is turned on (so not auto). Today I started to notice that they produce a lot of noise, sort of crispy when no music is playing. They automatically turn on (red light becomes green) when I play music from my Mac (Pro). Also one speaker suddenly turned on in the middle of the night when the Mac was off an it started making more louder crispy noises. Both speakers are next to a Samsung lcd panel (about 15 cm from the screen). Cellphone was off. 

Anyone any ideas? 

thx.