The sound is broken because of some stupid game mechanic that “hides” the sound of a tank if you’re “keen vision” skill is too low.
Here’s an idea that would actually make sense. Lower the tank sound to 50% for an untrained crew to “simulate” inexperience and increase it up to 100% for a fully trained crew. Took me an entire minute to come up with a better idea then whoever was sniffing glue when they came up with the shit show it is now.
And not rendering tanks to combat cheaters is not working. Dump that part of the code. Less to maintain, more time to fix the rest of the “bugs” (aka broken mechanics)