Restarting a PAX S300 and Checking Network Cable
The small headphone looking cable that is plugged into the small brick that is circled runs to the power cable that the arrow is pointing at. You will want to follow this cable to the wall to unplug power for 5 seconds and then reconnect.
The cable that is plugged into the reddish orange port is the Network Cable. Try unplug and reconnect this cable.