Humming noise when AUX is not plugged into laptop

I’m using an AUX cable (mini jack both ends) to connect my amp to my laptop. One end of the cable is always plugged into the amp, the other end is plugged into the laptop whenever I need a backing track or Josh’s voice in my head.

The problem is that the cable picks up a lot of humming noise when it’s not plugged into the laptop. Other than unplugging the cable from the amp as well (which I want to avoid because I’m lazy), is there a way to fix this? I’ve already tried moving the cable around (thought maybe it’s too close to the power cable or the instrument cable), but that didn’t make a difference.


@akos No. You need to switch off or unplug.
I have a multi socket on the back of my amp, so one switch and my full rig is off.


Oh well, unplugging it is then. Thanks


Does it happen when the laptop is plugged in to power and when it’s not plugged into power?


Haven’t tried it on power, only on battery. The noise goes away the moment I plug the aux cable into the laptop, no matter if it’s on or off. I only get noise when the cable is only plugged into the amp and not plugged into the laptop. (I guess it’s acting as an antenna then.)


Yep. It’s picking up the AC power which is background interference in most domestic environments. Either 60 or 50Hz.