Auto Detect (Dolby Digital 5.1) vs Expert Mode

I just installed a VIZIO M series soundbar.  X1 audio had been set to Auto Detect when using my old Samsung home theater.  Since the soundbar says it support various flavors of Dolby sound and since Comcast seems to recommend Expert Mode for best audio, I set the X1 audio to Expert.  When set to Expert Mode, there is a second or two delay in sound when resuming after a pause in the content that is playing.  This silence occurs with live TV, Recorded TV or any streaming service.  Except for the sound delay, I cannot hear any difference in the audio between the two settings.

I have seen many CLOSED posts on Audio issues.  I use an XG1v3 DVR.

Is this still a Comcast issue?