In order to sync Wearhaus Arcs, there most be a Host (the user controlling the music/audio).
Starting a Broadcast: The host must tap and hold the touch panel on the right ear cup to start the broadcast. The host will hear a beep once the headphones are broadcasting.
Joining a Broadcast: Double tap the touch panel for the headphones to start scanning for nearby station (after the Host hears the beep). The headphones will automatically connect to the nearest station. If you do not hear the beep to confirm that you have entered search mode, simply double-tap again until you hear the beep. If there are multiple broadcasts available, you can swipe left/right to skip through stations.
Here's a video demo for syncing using touch control: Getting Started: Syncing.