On standby the amps shut down. They were all designed to work like this (amps running full), except Beolab 50 and 90. So I don't think there's a problem.
You can check this by stopping the music and turning the volume all the way down to 0. You will still hear a small hiss in the speakers (especially audible from the tweeters). This hiss has the same intensity no matter what volume you set. And if you put them in Standby the hiss will disappear.
For PowerLink cables look for ones that have very good shielding connected at both ends.
