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=USUAN1100164

MacLeod's description:

Genre: Horror
Length: 1:12
Instruments: Piano

Slow and measured quiet pulsing piano. For that "something is going on... and it probably won't be good" feel. 038
ISRC: US-UAN-11-00164
Unnerving, Mysterious, Eerie 2006