General Bismark does this too. What I found helps but not eliminate the problem, is distractions.
He eats the same two wall areas. The wall in the area by his litter box, and the enclosed porch door.
But his poo box I have a big bowl I fill with hay. As long as it's full and fresh he does not seem to abuse the walls at all. However, if I notice there is more hay on the floor than int he bowl, he tends to go back to the wall.
For the door, I tried spraying him with a water bottle, but it on;y deters him for a few minutes and he goes right back. Nasty tasting sprays never worked with him. I have newspaper that I fold up, and when he tries to chew I place the newspaper on top of him. He's gets happy and drags it around the living room instead of chewing the wall.
Distract, distract, distract! A bunny who isn't bored or who has the munchies seem to do less damage.