i bought this kvm because there are very few with the exact specifications i need. this one felt very promising, and i didn't mind the high price tag.however, i spent six hours on this and was only met with failure and disappointment.my setup:3 x qhd 1440p / 144 hz monitors.1 x windows pc.1 x mac studio m1 max.1 x linux box.the disappointment:it was clear that as soon as i opened the box, this $599 kvm was previously used. it was scratched/scuffled, had something that looked like stains, the plastic wrap was already opened, and it was missing 1 hdmi cable plus several bands and hdmi covers (parts that were easily lost after opening). the cables were already loose and sticking out in the box. the attached images show what a new kvm looks like.the issues:while the video worked fine (3 x qhd 1440p @ 144 hz), there were severe issues with getting any usb connection from the target computer to work. it didn't matter which computer i focused on, it didn't matter which cables i used, usb will not work. since it came with 4 x kvm cables, i tried them all, and no usb connection would pass through the box. this meant that no keyboard or mouse would work.i also tried multiple keyboards and mice. nothing worked.i reset the kvm using its built-in screen. didn't work.i tried every step i could find online, their manuals, and looked it up on message boards, but nothing worked. i even tried a powered usb hub, as they suggested, but still nothing.i tried different computers on different ports, switching out all cables, and it again failed.either this kvm's design is flawed, or the previous owner on this new kvm returned a faulty device, or they messed it up, which was then sent to me.also, when using a powered usb hub, it actually powers the kvm. when i unplugged its power supply because its screen told me to reset the box, it remained powered on. if a powered usb hub is plugged in, the power switch doesn't turn the box off. this could be dangerous since two power sources can feed into the box simultaneously.this was the worst kvm experience i ever had, and this one was supposed to be the chosen one—to undo the evil of my previous kvm, which began to fail.this is a hard pass. and my search continues.