I have been using a mix between YouTube's music library and nocopyrightsounds.co.uk
They have awesome, updated playlists of different genres that can fit a lot of different content. nocopyrightsounds has a lot of techno or electronic music, but they are 100% royalty free! You might come across something from YouTube's library. There is way more variety there than you would expect.
Here are 30 songs I wrote own 100% . I am looking to gain attention by sharing these tracks with people royalty free once discussed and approved . If you like one or more and want to use them please contact me with the details and we can go further . I'm not gonna ask for money so let's start something big! https://soundcloud.com/therealchrisblackbeats/sets/the-list-1