Why isn't the video shown on the TV synchronized with the audio from the Sound Bar?
Why is the dialog output from the Sound Bar out of sync with the lips movement of people on the TV?
Most likely your Polk Sound Bar is connected to the audio output of your TV.
Modern TV's process massive amounts of video data while sending audio data to the bar. Therefore, there will most likely be a delay between the audio from the bar, and the TVs image.
Most TV's will have a Lip Sync or A/V Delay setting in the Audio menu to adjust for this difference.
Please refer to your TV's manual for more information and the location of this setting.