On BrightSign Players you can enable Restart on the Hour, which will allow your Playlists to automatically restart on the hour every hour. To enable this, please follow these steps:
Open the Playlist you wish to enable this on from Content > Playlists > Create/Edit
With the Playlist open, hit the green Save button
When the dialogue box appears, head to the Advanced tab
Tick the Restart on the hour box then hit Save