The Host Sync Button enables RMX to sync with the transport in the host software. When the Play button is activated in the host, all Host-Synced Parts in RMX will begin playing.

Host Sync locks to the Host Song Position, so if the transport is started mid-measure, RMX will begin playing at the correct position in the loop.

At the moment Play is activated in the host, Host-Synced Parts will respond as if they were in Immediate Mode. While the host is playing, Parts will respond to the Trigger Mode to which they are set.