The audio delay setting in the app can only increase the delay, so it seems you need that set to 0. 
 

Then look in your TV settings to see if there’s anything else you can adjust. Also turn off any image processing features - noise reduction etc as this all takes time to process and so will push the video even further behind the audio. 
 

It might be helpful to know what TV and Sonos devices you’re using are, and how the Sonos devices are connected to your TV.

For instance, if you’re using the line-in on a Sonos Five, or a CONNECT of some type, all analog line ins have a built in delay of at least 75ms or so.

However, if you’re using a digital input, an HDMI ARC or eARC of some type, there should be any perceptible delay. Which would suggest that possibly there’s something on the TV that’s delaying the output to the Sonos in some way.