i had the same problem untill i started shocking my chest.first thing i did was work out my chest once a week, droped my reps down to 4-6 range, heavy weight of course. do some dips, decline, flyes incline,decline,flat, flat db presses (once i started doin this chest really started to grow).make sure when your using db that u get a good squeeze at the top and a good stretch at the bottom. Good Luck on your training. Peace