i know you said you cleared you cache but check thiss
go to brave://settings/clearBrowserData choose advanced then choose all time then make sure to choose cache cookies and site shield then press ok then restart brave then see if it help
what is your platform and also you brave version go to brave://settings/help ? to get the version of brave
Do you have other extensions installed? I throw everything at youtube, and it functions fine. Brave shields as aggressive, Privacy badger, and Ublock Origin are all protecting me from letting youtube make any money from me.
You get the same result after shutting the browser down and starting it back up?
If so, was the browser hijacked by some tab you always load?
If you open up a group of tabs each time, if one of those tabs have something on them that’s up to no good, that’s a hijacker. Often after you have one of those sites open, you’ll have a new tab popping up making money for them. So, if you close all tabs, shut Brave down, restart it, the same problem occurs?
Also do you use a VPN that’s also doing some filtering?
If you have no clue, you really need to give more info. Operating system and Brave version, as the minimum could be helpful.