I just recently got my Volca Beats analog drum machine and wanted to
sync it up with my Analog Four. To enable Volca Beats to sync with
external device using midi you need to make sure that clock source is
configured to auto.
While holding down func key and power on the volca device, you will
enter configuration mode of the Volca Beats. Pressing play button
will cancel any changes, record will save the changes and reboot
your device. The configuration of clock source is done with step
button 6, if this led is lit, clock source is configured to auto
which is needed to sync with external midi clock.
You also need to configure the Analog Four to send midi clock and
transport midi messages. Access the global menu using the combination
of func + C2 keys. Navigate to menu entry MIDI SYNC and hit yes
button, then set the send midi clock and transport. Hit no button to
get back to global menu and enter MIDI PORT CONFIG menu. Make sure
that OUT PORT FUNC is configured as MIDI.