You must be knowing about the restrictions that YouTube has plans to impose on its users in certain fields but strangely they have a site where one can covert YouTube songs to MP3 and save them. No questions asked. However, if songs have a copyright automatically those will not download.
I was searching for some Christmas songs and I could get the latest nonstop collection which I stored in my pendrive That came in handy for the party I had organised.
YouTube is sure is a mystery.
Did you know about this YouTube link?