When I try to change any option in 'Audio' tab, game just crushes and close itself.
I found a workaround to that issue. Just simply modify following lines (masterVolume, musicVolume, effectsVolume,
dialogVolume, inputVolume) in file:
C:\Users\<user_name>\Documents\My Games\Titan Quest - Immortal Throne\Settings\options.txt

Same for me.
Thanks for help.

Same for me. The workaround seems to be working. Thanks for the tip

Thank you! Same issue was happening to me as well

Hey
I've made an util to workaround this issue. With it you can adjust sound levels just like in the game. Note that TQ must be shut down or sound changes will not apply. Though it's not very comfortable but still little bit easier than to change config every time.

Below are the links to screenshot, zipped exe and zipped solution for visual studio, in case if you want to build it by yourself:
screen: ti nyurl. com/y52yqv26
zipped exe: ti nyurl. com/yxlkx7j6
zipped solution: tinyurl. com/y3av5lw3