ok well my squak has got onto this habit when sitting on my shoulder of starting to be obsessed with my ears, he nibbles on them but sometimes it gets a bit hard and it gets annoying, you put him down after that , but then he climbs back up your arm and onto my shoulder then its ear time again,

, hes only about 4 months old
any suggestions to stop this or any one else had this problem , its getting to the stage where i dont trust him on my shoulder, its not a viscous bite its just nibbling but at times it gets a bit harder