My Huawei Mate 20 Lite repeatedly and suddenly spontaneously reduces the sound while watching YouTube videos. Can this be deactivated somehow?

Do you have that too? It's only with me, my father and mother who have Huawei, maybe that's the case with Android in general. I'm not sure.

It is quite annoying, can't use the message that listening with headphones that are too loud is harmful, as it is a little different for the hearing impaired.

This is normal, even the mate 20 lite can't be switched off, this is a "security" that can't be removed