Apple music spatial audio only played in 5.1 audio on 7.1 speaker setup

I'm listening apple music spatial audio / dolby atmos on macbook pro 2019 connect to usb audio interface that support up to 10 output. I can play dolby content but only 5.1 not even 7.1 . I do a speaker configuration in Audio MIDI setup and set for 7.1 rear surround. How do i able to listen to 7.1 spatial audio in apple music because dolby atmos is not channel specific. I can do mix dolby atmos music in Logic Pro with 7.1 speaker setup