hottobar wrote:I moved my VM to Qemu and I suggest anybody affected to do the same.
FWIW, I have just done the same with mine. It's not entirely trivial; and then I am well versed with KVM/QEMU/virt-manager, having used these extensively over 5+ years, albeit with Linux and BSD guests.
Performance seems comparable at first glance. Some convenience features are definitely easier with VirtualBox: dynamic guest display resolution adjustment to virtual console size and shared folders are two I noted; until I get used to it, I suppose. Oh, and it's definitely easier to setup bridged networking in VirtualBox. With KVM/QEMU, I had to resort to NAT as I couldn't figure out how to set-up a bridge with my WLAN NIC without replacing NetworkManager with systemd-networkd, which would be a pain for things like switching WiFi networks among others.
Anyway, if there's interest I can post the steps I used for the VM conversion.
mpack wrote:If none of this makes a difference then it doesn't look like a VirtualBox related problem.
The fact that my Win10 VM, which used to work fine under a very close version of VirtualBox but on different hardware (Ryzen 3700U vs Intel Tiger Lake), now also works fine on that same Tiger Lake hardware but on a different hypervisor, certainly does suggest that there is an issue with VirtualBox. Many of the reports on this thread explicitly mention Tiger Lake/Ice Lake CPUs so a correlation looks likely IMHO.