[capt_noonie]

If he is teething, that may be why. If he's not, it could be behavioral. He may be acting territorial. He may have a favorite toy and get mad when its taken away from him. My Uni was growling whenever you get close to her when she was chewing on a toy, but it was because my bro in law was hyping her up to growl when he tried to take her toy away. What I did was when she had a toy, I came up to her towards her tail, and petted her, not trying to take her toy, being very passive and calm. Say good girl, and just hang out with her. Do not try to take the toy away. Eventually she started to trust me that I would not take it away from her, and she let me slowly take the toy from her mouth because she knew i would give it back.

If he is biting the couch, or blanket on the bed, when you take away the toy, it just means he is frustrated. He was just biting something, and it's gone, so he says "hey what else can i bite now" and he will bite whatever that is in front of his face.

When my Uni was teething she was biting the baseboards by the carpet, shredded the drywall, tearing it off in strips! If they are teething, just let them do it, they need to bite!