I've found that sometimes I have to set the sound options in the Netflix app. Netflix gets this question daily so be sure to ask them as well. Again, this question is well worn but the exact answer varies with the tv and Netflix. My answer from last year may work but many consumers want a step by step. For that, you ask Samsung at 1800samsung.
Bob
I have a Samsung 6 series led 6350 tv and a Samsung hw-h550 sound bar. When I use the smart button and watch Netflix the sound doesn't come out of the sound bar I have to turn on the regular tv speakers to hear anything and don't know why Netflix doesn't play out of the sound bar?? Also when I turn the tv off the sound bar turns off but when I turn the tv back on the sound bar turns on but it always is on the D.IN source and I always have to click the remote back to HDMI to get the picture and sound back on. I use two HDMI cords One from the cable box to the SB and one from the SB to the TV. Can somebody please explain if this is possible to fix so that when I turn the TV on my soundbar is automatically on the HDMI setting and why my sound isn't comin through when I use Netflix on the TV

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