Additionally TM runs on thousands of different hardware configurations which always can cause unexpected behaviour.
Of course it would be best to have software complete free of bugs but it`s not possible because it would take too much time and that is a very important factor. If the developement of TM took 10 years+ because they want to make it completely bug free they would loose most of their customers.
And one last thing: the developers are humans and humans always do mistakes. Again it`s a matter of time to find all mistakes and fix them but sadly our time is limited.
PS: I do not have any problems with the sound ingame. I can imagine it is not easy to find the bug if for some it`s working and for some it`s not

Btw did you check your sound settings? The volume of the sounds got a lot lower with the update so you have to set your volume higher to get the same sound as before the update.