Hallo Barry,
Thank you for your investigations. The problem is that I check the input of x(n) and generate not an default array for that. So if you put an array with the same number of values, with start value 0 and step 0, it should work (all ports connected to avoid side effects). I am waiting till next alpha of the @'y'@ to find a better solution, because Max has announced big changes in value handling - maybe he will integrate some better solutions by himselve? I'm very curious:-)

Kind regards
Karsten