hi , thanks for reading.....ive had a very odd fault on two parts of these speakers, my son was getting shocks when he touched his MacBook Air or mic or his audio interface , when he was at the same time touching his guitar which was plugged into his amp , his setup is quite straight forward....cr5x monitors. ...2 x xlr leads to his presonus usb interface with a shure sm57 mic on his amp .(usb powered from laptop)...Mac bookair laptop...no charger plugged in...just on internal battery...so these speakers are. " double insulated". i.e. no earth, the mains cable is just a two core live and neutral...so as you can see from this setup there is no earth at all..his electric guitar is plugged into his orange amp and is earthed..via three pin mains plug..this earth is right through to the guitar strings !!..so with my volt meter (fluke digital) I tested from any metallic part of the speakers..including all the screw heads on the back panel of the side with the mains voltage going in to it..to a known good earth terminal..at the wall socket and I get around. 90 volts ac !!!!way above what I would think was acceptable...I sent the speakers back to amazon and got a replacement pair.....I tested them straight out of the box and found exactly the same fault....I got in touch with mackies service dep here in the u.k. and was told this was normal with switched mode psu,s.and some people are more sensitive than others ! and was told just to make sure that I earthed them properly !!!! not sure how I can do this with this setup, there isn't an earth terminal on any part of it !...the return path for this earth fault is straight down my sons arm...so he darent even use them..!!! I send them a video/photos of the test results..but now they've just gone quite about this , , its a little bit worrying to think they aren't bothered !!! I have since got him two krk rokit5 speakers , each one with its own three pin main plug so therefore earthed, and he now no longer is getting electric shocks !!..I wonder has anyone else come across this, or maybe everyone that has these speakers has them plugged into some other equipment that is earthed, so therefore wouldnt be aware of this stray voltage ???thanks for reading ...mark.