This has been sitting in the Pd-extended bug tracker since 2010-01-21 20:08:33 PS
Hans' comment suggested it should live on this bug tracker, so here it is.
(Originally Pd-ext bug tracker #ID: 2936861)
Pd version 0.42-5extended-20091215
If you pass a pix signal trough a pix_puzzle the image gets scrambled like it is suposed to, but if you cut the connection the image stays scrambled even if you delete pix_puzzle.
It goes back to normal if you bang pix_puzzle when the sinal is not passing trough.
It is not very problematic