Sound setting for G5

I am unsure of sound settings. I have a Sonos Beam but I have been keeping with auto settings. According to the Sonos app the Beam processs sound as Dolby Multichannel 2 or Dolby Multichannel 5 1. I can also choose Passthrough or Dolby Plus on HDMI settings. Should I keep with auto or passthrough settings as they sound the same?