ZynSeq uses JACK timebase for its timing. Transport control and adjustment of tempo may be made by external JACK clients. Those clients may also use the same timebase. This means that ZynSeq can synchronise with other modules within Zynthian, e.g. synth engine LFO, arpeggiators, etc. It also means that other modules may control ZynSeq playback to some degree. ZynSeq acts as the timebase master, i.e. the concept of bars, beats and ticks (fractions of beats) and consequently tempo (BPM) is provided by ZynSeq. There is currently no mechanism to lock to external MIDI clock but a Zynthian MIDI effects layer may be used to create MIDI clock output. There is a plan to improve this support in a future update.