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=USUAN1100849

MacLeod's description:

Genre: Horror
Length: 4:25
Instruments: Synths

Screeching dark, electronically chattery. Nightmarish.
ISRC: US-UAN-11-00849
Dark, Eerie, Mysterious, Unnerving 2011