The sound processing is why. This has been beat up so many times that you need to try an analog output on the TV next.
Bob
I am getting a 1 sec or so echo (delay between the tv speakers and the soundbar speakers) on my new panasonic sc-htb580 sbar. It is connected to my TH-50PX75U panasonic plasma tv using a digital audio optical cable. The TV is not hdmi-arc compatible so I needed to use the digital audio connection. I have tried changing all settings on the sounbar, as well as all settings on the tv, with no change. There is a 1 second or so delay between the tv speakers and the soundbar speakers. Any ideas?

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