Problem with Audio Settings-Volume

I hops someone can help me with this one.When going into the Audio Settings while playing film there is one setting which refuses to “save”
The Volume setting is stuck on -30.0db.
If I change it and then “Set as default for all media ” its fine for that session.
Once I have logged out and gone back in however it has reverted to -30.0db.
I have tried every setting within Kodi but nothing fixes it.
I am running Kodi v21 on Fie Cube v2.
I have tested various skins with the same results.