Music by Kevin MacLeod. Available under the Creative Commons Attribution 3.0 Unported license. Download link:  https://incompetech.com/music/royalty-free/index.html?isrc=USUAN1200055

MacLeod's description:

Genre: Soundtrack
Length: 3:12
Instruments: Strings, Percussion
Tempo: 90

I piece unlike anything I've done, this is a very difficult piece to process emotionally. It just never lets the audience rest. There are a lot of uses for this sort of piece. It is also available with just the percussion, and just the strings... both of which are quite different from the combined. ISRC: US-UAN-12-00055 Dark, Intense, Relaxed, Suspenseful, Unnerving 2012