Scraping noise
Scraping noises that can occur between items of equipment, especially the accessories, emit high acoustic signals i.e. check the diver's acoustic status, the equipment's possibility for generating noises such as removable accessories (camera, suit or drawing board).
Tip: Avoid diving towards acoustically sensitive objects as the natural background noise is low. The acoustic signature of the IS-MIX and diver is hidden more easily by high natural background noise.