Ohhhhh I know all to well about this.
My Casper who is now 7 months old is doing this.
But my thing is we have done everthing LR has said.Except fpr the high pitched yowl.Since he is deaf,he can't hear it.
With Casper,he attacts.Ears back,head cocked.And this is in the middle of the room while we are on the couch.He'll be lovey and dovey in your arms,then attack and bite.And I mean very hard.Hubby(Mr no brains) tried to calm him down and put his face right close to Caspers,yup you guessed it,Casper got him right on the lip.No blood though.I actually had to put Casper in our room to settle him down.Both hubby and Casper needed a time out.LOL.
LR,we are still thinking on getting him a playmate.But I'm worried he will hurt her.Yes we are thinking of a female around the same age.
And this biting has gone on for a few months.