Hi everyone, I'd like to hear about your experience and get your advice if possible. I was able to test a second Z623 kit in parallel with the one I've just bought, and both suffer from white noise / hiss, even with the potentiometer at zero. I have good hearing, and I can hear it up to about 1m from the satellites. This is certainly tolerable for a lot of people, but for low-volume, close-up listening (which is basic on a PC!) I find it intolerable in this price range. I'm convinced that this is a design flaw, because all the sources are mixed; there are no switches. You can play sound (make mush) simultaneously in 3.5mm jack and RCA. And in my opinion, a source selector would have avoided this problem. And when no source is used, a hum appears in addition to the murmur. It's the same with an ungrounded source, such as a smartphone on the AUX socket. So my question, just in case, is there a way of silencing/shunting unused sources? Am I the only one who finds this so unbearable that I rush to switch off the speakers as soon as I'm not playing any sound? Thanks in advance!