Basically survivors doesn't make any sound 4.0.0
This famous Youtuber told everything you need to know.
• Platform - PC
• Description of the issue - STILL slugged survivers doesin't make any sound, RANDOM Iron will appearance, Iron will removes every breathing sound, No foot steps sounds in the certain areas, no down falling sounds, ect.
• Steps to reproduce (if possible) - impossible
• How often does this occur - very often