I have the same problem after updating Virtualbox. Reinstalling, updating, reconfiguring kernels, nothing worked. This is problem only with Whonix, Windows virtual machine works like before.
WHAT WORKED HOWEVER was manually making Whonix by making new Debian 64 machine and adding .vdi file as a hard drive. Then I would imitate original Whonix settings and so far it works, this is how I’m answering your question.
Is it problem with .vbox file? I don’t know, importing new Whonix machines didn’t work, just manual add.
THAT SAID PLEASE ONLY DO IT IF YOU KNOW WHAT YOU ARE DOING! Who knows if I configured it correctly, it works and Workstation is fully torrified but I would consider this method as quick fix, I hope some Whonix Developer will look into it.
I’m affected by the same problem since VB was updated. Host is Linux Mint 19.1. As said above, I tried to create a new vm with same settings, same vdi file, a valid uuid, no save state, but problem persists. Tried uninstalling guest additions pack, still a no.
I’ll keep an eye on this thread
I downgraded to Virtualbox 6.1.18 (before solution got posted) and will wait with update until it gets fixed, new version has mostly fixes not related to security.
Interesting thing because when I was updating Whonix Gateway (later just running) sound on the host would get corrupted when listening to music or playing video files. I don’t know what storage type I had in manual Whonix Gateway but if it was AHCI then this solution won’t help me. I hope it’s just temporary problem and I won’t be stuck forever on outdated Virtualbox version.
According to changelog it got fixed in 6.1.22
virtualbox DOT org/wiki/Changelog-6.1#v22
Storage: Fixed regression in LsiLogic SAS controller emulation caused VM crash (bug #20323)