I’m also interested in this as The same happens with my system . I have a 5.1 with a Yamaha amp, AE speakers and a Yamaha sub
Surround sound is fine and plenty loud to hear background music, shootings, explosions etc but when it comes to dialogue especially low voices or whispers then I really struggle and it gets annoying with having to adjust all the time. I did read that that’s how programme is made and there’s not a lot you can do. I’ve messed about with the settings and various sound programmes e.g music theatre, concert hall etc but still not much joy.