It is possible to detect when the output of added effect is different # channels or rate then the output of the previous effect in the chain.
It is an error case to insert in this case unless the add effect is marked as able to handle the conversion. We should add this error check in.
Try "./example1 monkey.wav monkey.cdr" as an example of creating an invalid file that above fix would at least
indicate to user that it can't be handled.