I have a 2 year old cocker spaniel who l would say is fairly well trained and is an absolute joy to have around (1st dog 
). However we have an ongoing problem with the postman and also when someone comes to the door he barks constantly and has now started to bite and chew the door to get at them. He is not being aggresive though -he wants t chew the letters from the postman not the man himself.
Even when one of the family are coming home from work/school and he hears us coming up the path he starts barking and crying, chewing the door until we get it Can l add that he is not alone in the house.
The barking when someone comes to the door is getting out of hand. We have tried removing him from the hall but he throws himself against the door to get at the front door.
Any advice would be appreciated-can l add that when the person enters the house he runs away !!!