ReactOS 0.4.10-dev-7-g0d308f4 with VBEMP, VBox 4.3.40, no guest additions
(with and without the ThFabba-patch from
It happens without AC97 installed, and also with working AC97 sound.
I noticed this the first time on 2018-04-12 with a revision > 0.4.9-dev-155-g9987f02917539e05268ba2ad11e62d24a3636972.
It's a regression as this used to work fine in 0.4.8rls.
The system was frozen in the end and I could not even ACPI-shutdown or open the taskmgr anymore.
A hard-reset is all that helps.
I will double-check again in a second (0.4.9-dev-155 vs 0.4.9-dev-154).