Sorting fails?

[mmuziek]

hello everyone.

i have made a sorting facility.

but it fails a bit.

i colored the pipes as it must be.

there are all connected to a chest.

and programmed in correctly.

but sometimes 1 fails and some even 2 pipes fails they just do not enter that pipe but the color and such are correct.

(see pictures)

http://img267.imageshack.us/slideshow/webplayer.php?id=20120307163658.png

http://imageshack.us/g/267/20120307163658.png/

anyone has any idea how to fix this?