I have been having a problem with my 2nd gear, every time i down shift into 2nd gear(3000-3500RPM) it seems as if it does not want to stay in gear and pops out on its own almost everytime, what is the cause of this?

 

Your cable may be poping out from the shift housing.

Pull out the center console and look at the cable hold downs. They are just plastic clips. They can pop out rather easily.