I have a sorting machine with 10 redpower sorters, but certain items don't sort correctly
eg:
Rubber tress logs
insulated redstone wire (all colours)
saphires
rubys
emeralds
(to name but a few)
The items come out of the sorting machine tagged with the colour i have specified (yellow) in the GUI for sorting machine but when they pass the pneumatic tube with the corresponding colour, they do not flow up it and so carry on along the same path that the items with the default tag (white) follow.