I had this issue on my desktop in Windows. Haven’t tested to see if it’s an issue on Linux (I just recently set up dual-booting with Kubuntu). I know your request is for Nobara but this may be helpful for troubleshooting.
The fix for me on Windows was always to power off my audio interface. Using powercfg /requests
would show Firefox kept the audio device active once a YouTube video started playing. The software fix was arbitrary… sometimes closing the YouTube tab would work, sometimes I had to close the window, and sometimes none of those would work. What *always" worked was physically powering off my interface, waiting about 2 seconds, and turning it back on.
There’s a few ways to turn it off, but they require registry editing or using the Group Policy editor if you have a Pro license
https://www.ghacks.net/2021/11/26/how-to-turn-off-search-the-web-results-in-windows-11/