After trying different things, I have mpg123 playing a mp3-file correctly. Appaprently, there's still a problem with xgalaga, which delays everytihing with +/- 8 seconds. It uses the dsp device but it may contain deprecated audio code.
current script to start NetBSD oin Qemu:
-hda /dev/nvd1 \
-net nic \
-net tap,ifname=tap0 \
-vga cirrus \
-smp 4 \
-m 16G \
-device ac97,audiodev=oss \
# Why does this block show black on white text?
I'm using Qemu for it's many options. Currently, I have FreeBSD and NetBSD installed on 2 different physical drives. They are able to boot eachother emulated with the same parameters except the drive name. . I still have to find out how the acceleration in NetBSD works. The FreeBSD system is still way faster. I upgraded NetBSD 9.3 to current from within Qemu for the 2.5Gbit Realtek network driver. Took 1 night but no problems at all.