That certainly is a very strange "problem".
One that I cannot reproduce. I think it's not a COPS problem, but probably has something to do with your QNAP. As I do not have one, I cannot test......
Maybe one thing, I (always) use "cops" (lowercase). Do you have the problem only with "COPS" (uppercase)? Not that changing "cops" to "COPS" made any difference for me, everything worked, but it just might help you.
If you ever figure it out, let us know!
