I installed the Murmur Server (Mumble Server), because OSEEurope has a bandwidth restriction in their murmur install (<50k per user) which reduces the quality for people with higher bandwidth WAN and average or high quality audio equipment, but the main reason is, that the Murmur server < 1.2.3 does not allow any audio recording.
So far I have installed murmur and configured it, but the installed version is 1.2.2, not 1.2.3, because the packages in the official Debian repository don’t contain the version 1.2.3 (was released last year! )
TODO: keep the /etc/mumble-server.conf and install the murmur 1.2.3 to be able to record a meeting.