DIAGNOSIS This is an HDMI handshake or signal integrity issue. The TV and soundbar are briefly losing sync on the digital audio signal.
FIX First, replace the HDMI cable with a certified Premium High Speed HDMI cable. Ensure it's firmly seated at both ends. On your TV, disable any advanced video processing for the HDMI-ARC port, like 'HDMI Ultra HD Deep Color' or similar, and set the output to a standard format like PCM or Dolby Digital, not Dolby Digital Plus.
IF THAT DIDN'T WORK Power cycle the entire system. Turn off and unplug the TV, soundbar, and any other connected devices (like cable boxes). Wait 2 minutes. Plug in and turn on the TV first, let it boot fully, then turn on the soundbar.
HEADS UP Some smart TV apps or external streaming devices can cause this due to inconsistent audio output formats. Try the same content from a different source (e.g., built-in app vs. game console) to isolate the problem to the source device.