sound is decreased in youtube Tab In safari, but in chrome iit is normal

Welcome Priyanshu53,

Have you tried to clear Safari's history yet? If not, try that now: Clear your browsing history in Safari on Mac - Apple Support

Clear your browsing history in Safari on Mac

You can remove all records that Safari keeps of where you’ve browsed during a period of time you choose. If your Mac and your other devices have Safari turned on in iCloud preferences, your browsing history is removed from all of them. Clearing your browsing history in Safari doesn’t clear any browsing histories kept independently by websites you visited.

1. In the Safari app  on your Mac, choose History > Clear History, then click the pop-up menu.

2. Choose how far back you want your browsing history cleared.

Should it persist, YouTube has its own volume control within the video. In that YouTube tab, are you able to adjust the volume? Is it video specific or happens with all videos on the YouTube website?

Hoping to hear back, take care.

Hi priyanshu53,

There is no independent volume control in Safari. Does restarting the Mac help? Sometimes this helps with minor software issues? Have you checked to make sure that the volume of the video itself isn't low in Safari? YouTube retains volume preferences. So if you watched something at a lower volume previously you'll want to check that.

We hope this helps.

Take care.