Fixing broken keyboard configuration, debian on VirtualBox on void

I have debian running on Virtualbox. Host system is also Linux (void). Computer is Lenovo X220 with an US keyboard. On the host system keyboard works very well. All keys work as expected. Both host and guest run Xwayland with gnome-session. However on the guest system the keyboard is somewhat broken. The number keys don't work at all, and so don't the special characters on those keys with shift pressed. When pressing q it yields /, / produces p and p delivers q. x and z are swapped and so on. setxkbmap -query brings WARNING: Running setxkbmap against an Xwayland server rules: evdev model: pc105 layout: us on host and guest as well! I have absolutely lost any orientation. I miss any clue where to set the physical keyboard, which must make the difference here. As far as I understand VirtualBox relays all physical keycodes without altering to the guest. So there must be some differences in configuration but I really don't know how to set or even find them.