The new feature with input on multiple staves is great - especially with midi input. But I only hear the sounds from the top selected stave.
It’s a bit complicated to make this happen, because Dorico needs to echo the note back to you as quickly as possible so that you don’t feel that there is a high input latency. But Dorico wouldn’t be able to work out which sound to use for each note you play until it has fully processed the input and determined the destination for each note, which takes a non-trivial amount of time, and would I think lead to a perception that there is a long delay between playing a note on your keyboard and hearing the pitches echoed back to you.