Fedora 35, KDE Plasma.
I have Firefox browser opened. YouTube videos are opened in several tabs.
I open Audio Volume control. Devices / Speakers = 80%, Devices / Headphones = 80% (tried both). Applications / Firefox = 100% for all tabs.
Then I start playing video in a browser tab. Once it starts, the sound volume is automatically dropped: Applications / Firefox = 77%. While the video is playing I manually return the volume to 100%. Then after some time I pause the video. Then on resuming it the volume is immediately dropped: Applications / Firefox = 77%.
This occurs on every video start / resume. What can be a reason? How to stop this? Thank you.