I think that Hama here noted that Tani uses a higher tone ONLY when talking to ADMIRAL compare to when talking to her. And she sorta realize the reason behind it (which she diverts into how Tani has a pleasant tone).
And Saber here, being as straight as she is, immediately pointing that out for Tani, boiling the poor girl in the process.
*I heard somewhere that you are more likely to use a higher tone when either you want to appear cuter, weaker, obedient...toward the opposite or the person you like. Which means that Tani here might have a thing for her Admiral. Getting pointed out by Saber embarrassed her.
*I heard somewhere that you are more likely to use a higher tone when either you want to appear cuter, weaker, obedient...toward the opposite or the person you like...
Can confirm. I talk like that only in the presence of my girlfriend.