DND on iPad or iPhone

I feel like a newb because I can’t figure this out.

Watching any video or streaming. If a text or email comes in to me the video stream audio fades out a bit and then comes back normally. But the constant fade in/out can be annoying.

What am I doing wrong?

Have you tried turning on “Do Not Disturb” while watching?

Have you tried to set “always” under dnd settings?