One Piece receiving two "copies" of single GCK?

I have a piece that sometimes seems to pick up two copies of a GCK sent to it, even though the GCK is only sent once (I’ve logged out the sending and receiving – and while it often works right, I sometimes see two “incoming” for only one “outgoing”).

My only clue is that the GCK does move the receiving piece – could moving it somehow put it back in line to maybe receive the same GCK an extra time?


And a sub-clue is that when the piece is moved, it sometimes ends up “stacked” with another piece – could it be when it is put into a stack that it is sometimes put back in line to receive my original GCK for a second time?

I guess I’ll have to find a different angle of attack (i.e. send it its desired final destination rather than sending it “how much to adjust itself”).