Chewing plastic litter boxes

[Alexnv]

I have two bonded neutered male rabbits. One is a lop and one is a lionhead mix. My lop has been chewing on the side of his plastic litter box excessively. I use an under the bed storage box lined with a pee pad clipped to the sides. This has never been an issue before but now it has become a big one.

Here is what I have done to prevent this issue:
Moved the litter box to a different corner (This did fix it for a few days)
Clipped a bit of balsa wood to where he chews (This also fixed it for a few days as he would remove the wood and go chew on that each night)
Sprayed the area with bitter cherry (This did nothing)
Increased the amount of chewing toys he has access to
Saw a vet to check his teeth (he is fine)
Rotated the box (he chewed the exact same spot)

They are both semi-free roam (free roam restricted to a bedroom and bathroom)

 

[Blue eyes]

Could you post a photo of the box with where he's chewing? Is the pee pad clipped on that area too?

One possible solution can be found here.
https://www.rabbitsonline.net/threads/destroying-litter-boxes.101098/

 

[Diane R]

You can get stainless steel litter trays. Pricey though. https://www.amazon.co.uk/Yangbaga-L...a-943985708776&ref=&adgrpid=100431048939&th=1