When ARC-8050T3U firmware is not properly started up, the LEDs will have this kind of behavior. This situation comes from the thunderbolt standby state corrupted. Please execute a clean force power on test to see if it works.

To do a clean force power on test, please follow these procedures below: 
1. Disconnect the thunderbolt cable and the power cable from ARC-8050

2. Connect power cable to ARC-8050

3. Hold the reset button on the ARC-8050 back for 4 seconds

If ARC-8050 starts up correctly, please hold the reset button for 4 seconds one more time to shut it down, then connect ARC-8050 to your computer to see if it works now.

If ARC-8050 failed to start up, it would be a hardware problem and needed to be repaired. You can contact your supplier for repair assist.