I have the same problem with dolby if i ask nokia to revert my phone back to nougat,
the camera app will be the old one or that from Oreo?
Yes If you downgrade to Nougat Rom you get old camera app (Not the New one from Oreo).From my liking Nougat rom had punchy colors for the Display and also had Cleaner but not louder dolby atmos.Its your Choice.But Audio quality on oreo is bad which irritates me a lot.
Clethan, I have experienced exactly the same problem as you. After the February update, it has not been better, I even feel it gets worse. My only way is hoping the forthcoming update can fix this bug, I dont want to downgrade to the Nougat.
I also have a hiss even without Dolby, especially in the top dynamics. When they solve this problem, who can say?