music autoplay on profile?

i before had a song playing on my profile just fine, it was a link from youtube, but i just recently (tried to) changed it to another one, and it isn't playing. the song doesnt have any silence in the beginning, so maybe im wondering, and this is rllyyy dumb and i just KNOW its not the reason but it COULD be, that maybe songs from ur own channel dont work..??? idk... that's too dumb to be it because how would it know if its ur channel.. so idk..!!! help!!