We thought my previous bunny, Buzzby, was deaf because he showed absolutely no fear of noise, the lawnmower, grinder etc in the garage next to the patio, no fear. It was even more certain when we realised if he was cleaning and couldnt see you coming (lop ears seemed to get in the way of some of his vision from behind too) he would leap out of his skin when you got there, before coming for nose rubs. I gradually got used to making sure I waved frantically before getting too close so he caught sight of me and didnt panic. When he was in his bed area and didnt know I was there I would bang on the floor so he could feel I was there and soon learned that meant he could have cuddles! By the end of the wonderful time he spent with us we were certain he was deaf but other than being considerate of it and making sure he knew we were coming it did nothing but make him a bolder happier bunny.