Have a new Z9S for 3 weeks. Dolby Atmos worked fine until the latest update. Now it does not output Dolby Atmos. It worked fine before. I did not change any settings. Audio is set to RAW. Anyone else have this problem. Still within my 30 days so I can return it and try another unit.
Do a factory reset and try out again. If it doesn't solve repeat more than one time the factory reset until it works again. Reinstall the firmware upgrade even if it shows that the box has the latest firmware.