Many of these soundbars will be silent if you send them 5.1 audio. Try PCM or Stereo. If that fails, try the soundbar on other devices to sniff out if it's the TV, cable or bar.
I have a Samsung tv (PN50C450B1D) and sound bar (HW-J550) above my fireplace. TV does not have hdmi arc, so they are connected by optical cable. HDMI connected to TV comes out of our wall on the other side of the room. From there, that HDMI cable runs into a Rocketfish switcher. Then cable box, Apple TV, and Sony DVD player are connected to the Rocketfish switcher. Everything was working fine (albeit we had several remotes we were using), then we had to disassemble everything because we had to clear out the room to have our carpet replaced. Now that we've reassembled everything, we only get sound when we toggle the Rocketfish switcher to Apple TV. No sound when we toggle to the cable box or DVD player. We thought maybe the Rocketfish went bad, so we changed up where we input the HDMIs into the Rocketfish, but same problem...still only got sound when we toggled to Apple TV. Thoughts?? TV video is set to HDMI and audio to Digital. TV also set to audio through external speakers. Thanks all!

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