1. Be sure any cable end caps were removed.
2. Get out your canned air and give the optical ports the shortest blast you can.
3. Try PCM or Stereo on the source.
Bob
My sound bar on occasion will not produce sound when turned on by the auto-TV (or manually for that matter). Its hooked up to a samsung TV via a optical cable. The only way to get the sound bar to work is to unplug the unit from the power (120 vac) , disconnect the optical cable, reconnect the optical cable, count to 10 and plug back in. The firm wear has been updated and cable replaced.

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