Im maybe dumb, but could it be Morse code?
Something like thisโฆ
http://www.livephysics.com/tools/mathematical-tools/morse-code-conversion-tool/
https://youtu.be/9JR0V41vH2Y?t=537
Anyone seen this before?
This guy decodes images and songs in Cicada 3301 and find Q reference before Q gets public?