Ubuntu20.04 mouse disappears and keyboard not work on virtualbox

[Ren]

Hello! This is the first time I posted here so I am sorry if I made any mistakes when posting.

I searched online for a long time but do not find the same problem so I think my question may be new.
I installed ubuntu20.04 recently on VirtualBox, with the host of Windows 10. Now I found that, when I left my laptop alone for some time, the ubuntu locked screen automatically. Then I unlocked it. But after logining/unlocking, the mouse disappears and keyboard does not work at all on ubuntu. Mouse and keyboard can work in my windows host but not on ubuntu.
I can see the ubuntu screen as normal and its time still goes on so I think the system does not freeze. But it does not respond to any input from mouse and keyboard. I have no choice but to power off. But this problem will happen again after some time. I also want to mention that this problem only happens when I unlocked the ubuntu after some time of no operation. If I power on the system, it will not appear and everything looks okay.
I have enclosed my system log for your reference.
This is some info about my system:
Virtualbox version: 7.0.6 r155176
Ubuntu version: 20.04

Could you help me fix this? Thanks in advance.

Best,
Ren.

[mpack]

It sounds like a typical example of adding a USB filter set so broad as to grab everything on the host USB bus.

[fth0]

I haven't read the whole syslog, since I didn't want to guess how it corresponds to your description (what happened when). But I noticed two aspects that may or may not play a role:

1. You've been using (X)Wayland, which isn't fully supported by VirtualBox. Try if the issue persists when booting into X11 instead of Wayland.

2. You've installed NoMachine for remote desktop sessions. Try if the issue persists after uninstalling NoMachine for a test.

[Ren]

I haven't read the whole syslog, since I didn't want to guess how it corresponds to your description (what happened when). But I noticed two aspects that may or may not play a role:

1. You've been using (X)Wayland, which isn't fully supported by VirtualBox. Try if the issue persists when booting into X11 instead of Wayland.

2. You've installed NoMachine for remote desktop sessions. Try if the issue persists after uninstalling NoMachine for a test.

Thank you! I have switched to x11 and uninstalled NoMachine. I will wait to see and give updates here.

Update: This problem did not appear again but the system began to crash from time to time. So I decided to reinstall a new ubuntu system.

[Ren]

It sounds like a typical example of adding a USB filter set so broad as to grab everything on the host USB bus.

I think this might be an annoying problem. Not big but hard to identify/resolve...

[mpack]

A broad USB filter is very easy to confirm and resolve, just not with the info you already provided. You would know if a USB filter was configured (in VM settings |USB), and you would know how broad it was. My comment was intended to cause you to consider these things.