Well for me it is exactly opposite. It _immensely_ breaks my immersion if my character does _NOT_ speak his/her lines. I actually fail to even understand how it can break immersion for someone if he/she does but if yes - I agree they could simply give you an option to turn it off. Lucky for you, that's a lot easier solution, than what I need to be happy.
This means that you are satisfied with the voice and intonation of your character, because they coincide with what you imagine. For me it pisses me off because they don't. The voice is boring. The intonation is wrong. This breaks my immersion.
