Hi.
After a while, the mouse pointer begins to tremble in the guest system. When you leave the guest window, the jitter stops. When you return to the window - the jitter resumes ... For a while, avoiding the jitter helps reboot the guest machine.
I will be grateful for any help.
Host: Linux lx-station 4.4.0-66-generic #87-Ubuntu SMP Fri Mar 3 15:29:05 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
Guest: Linux mnt-wl 4.4.0-72-generic #93-Ubuntu SMP Fri Mar 31 14:07:41 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
Installed virtualbox-5.1 5.1.18-114002~Ubuntu~xenial with addon pack in host system and guest.