It seems Zoiper will not adhere to my Do Not Disturb (Silent hours) settings. It rings in the middle of the night while everything else remains quiet.
I'm using a OnePlus 6, on Android 8.1.0.
We have tested Zoiper against the pure android in all Google phones and some other brands, it should follow the system DND settings, unless there is some customisation by the manufacturer which behaves differently.
Thanks for your answer... I seem to have DND working right now. Best regards,