Is this just to do with his age and a case of me reminding him that I'm the boss?
By showing him I'm boss I don't mean hitting him or anything! When he bites at the lead I tell him he's bold/leave it and stand on it so he doesn't have enough slack to jump up, fold my arms and turn away until he calms down. For his recall and other commands I've been practicing with him again and again and loads of praise when he gets it right. Of course when anyone we know comes by he does all his tricks giving the paw and rolling over etc and flashes his puppy eyes at them and they tell me he's so good and not bold at all!

