Not sure if this can even be feasibly fixed, but certain keyboard layouts, in my case Polish, press multiple keys at once sometimes.
When I press Right Alt, the keyboard layout also automatically presses left control, as seen in the video. This results in mechakeys detecting two inputs and two sounds played, which sounds weird.
As I said, not sure if this can be fixed or if it's even worth it, just wanted to let you guys know that this happens sometimes...
