You will have to forgive me, I am kinda new to bowhunting and dont really know all the proper terminology. I shoot a Mathews Outback and recently began having problems with my peep sight. I have the peep sight with the rubber tube attached. First the tube kept coming off. I kept putting it back on and then my sight popped out of the string. I took it to the pro shop and had it put back in. After I got home, I shot about 10 times and the same thing. The sight popped out again. What could be causing this and what can be done to fix it?