Did you actually do any setup and configs on that Pio?
That Pio was new to the market ~15 years ago. So, have you ever set up an AVR of this vintage or newer?
Newer AVRs are much more complex than the old stuff, so if you don't have experience here, that is likely the problem. It isn't terribly difficult, but not quite trivial either!
I mentioned in your other thread, I have been running that same model Pio for ~15 years, several hours per day, every day! Was my main living room AVR for a long time, been on bedroom duty the last couple years. So, while its feature set is dated, it still a heck of a beastly AVR! My biggest complaint is that the thing is so dang big it will never fit in any modern AV furniture! Mine is on an open Sanus rack.