The configuration of the audioserver reference system forms a starting point for custom configurations of the netsim software.
Systemd service definitions are defined in the files netsim/configs/audioserver/systemd, which will initiate the various processes in the netsim system in the correct order.
The Jack Daemon launch file (jackd.service) initiates the Ultra 8R sound card on the audioserver test rig. This sound card driver has a bug that enables all channels in ALSA (including the internal crossover channels that feed audio from one input to another output) at maximum volume. Thus, this service first runs a script (fix_fast_track_levels.sh) that turns off these crossover channels. When using a different sound card, this will not likely be required.
For more information on configuring systemd service files, see the official documentation: https://www.freedesktop.org/software/systemd/man/systemd.unit.html.
Configuration for the netsim processes is stored in netsim/missions in the various *.pb.cfg files (in Protobuf TextFormat).
To see the available configuration from any of the Goby processes, run it with the -e flag, for example: netsim_manager -e.