I posted a few tips on this thread here;

https://drycounty.com/jovitalk/bon-j...ty-mp3-t70336/

-Get DVD Audio Extractor. (http://www.dvdae.com/)
-Rip to WAV first, keeping settings (such as sample rate) "same as source" anywhere possible.
-Convert to MP3 at 320kbps (I use dBpoweramp for this personally (https://www.dbpoweramp.com/)) which pretty much preserves DVD Audio quality
-Delete original WAV files if you want
-Job done

Sometimes the volume varies on many DVD's but that can be fixed very quickly with MP3Gain (http://mp3gain.sourceforge.net/) which doesn't require any re-encoding or loss of quality. It just boosts the volume on your existing mp3s and any changes can be undone.
Or if you use Audacity (https://www.audacityteam.org/), it has an "Amplify" option which does basically the same thing.