When you see the Source Lights cycle on your Dolby Dimension it is in Source Select mode. In this mode, you can press any of the Source Buttons to reconnect to your paired source devices or press and hold any of the Source Buttons to put Dolby Dimension into pairing mode.  Whenever Dolby Dimension disconnects  from a Source Device, it will go back to the Source Select mode unless placed on the Power Base or put to sleep.