I have a 15" MacBook Pro 2016. I mostly use it connected to a monitor and with an external Apple keyboard (usb). The keyboard is connected using an Apple USB to USB-C adapter. I regular experience malfunctions/delays when using ctrl, alt or cmd with other keys or mouse-clicks/moves. This causes issues with panning, rotating stuff (3d apps), moving things around the screen etc. It happens in any application (Photoshop, Finder and 3D applications). I use a Wacom for a mouse, but don't believe that's the issue. I have the same issue both in the office and at home, with different keyboards, different screens, different Wacoms – and whether the keyboard is connected directly to the MBP or through the screen etc. I get's so f annoying that I wan't to through the keyboard out the window at times. Anyone else has issues like this (not the trowing things out the window thing) – or better yet, a solution to the problem?