Definitely take the advice of just slowly letting the chin get to know you.. Imagine the chin is a very very shy small child.. Talk to the chin, sing to it, just sit by the cage and hang, read a book, watch tv, whatever.. Just gave o give them time to know you're a friend and not going to hurt them..
My oldest chin had a biting issue till very recently. I googled for hours trying to figure out a way to get her to stop, she was at the point of drawing blood and I had refused to handle her. My husband had the duties of playtime, etc.the trick to getting them to stop biting is to not react when they do. Don't yell, drop them, jerk your hand away, don't give ANY type of intense reaction. When you do that you either A. Spook them more causing them to bite harder or B. Show them that "ohhh if I do this then I get my way, they'll leave me alone!" chins aren't vicious creatures, they only bite as a means of manipulation. They say the easiest amd quickest way to stay calm when they bite is tobuy a leather glove and wear them whenever handling your chn (after there acclimated to their new house and you of course). That way they can bet all day and you wont feel anything. I personally would rather spend the money for gloves on treats fit them so I just made sure to stay disciplined and just not give her any reaction when shed bite. It took a couple weeks but I am proud to say My fingers ave been chinchila teeth free for a month and a half now! :0)