sandstone pipes are made not to connect to anything except other pipes. they're specifically so that you can route pipes around chests and hoppers without going into them.
also, if you have a T-intersection in the pipe, the item will go down the other fork instead of popping out of the pipe, so you can make a loop in the pipe that the item goes down if the inventory it's trying to go into is full.
edit: also if you can take a screenshot of your setup it'll be much easier to help, ascii art is kinda difficult to read.