[Windows 10 App] Random Changes to different devices and songs I never heard of before

[suffnocate]

Plan

Free

Country

Germany

Device

Desktop PC

Operating System

Windows 10

My Question or Issue

I can't really use the desktop app for Windows 10 anymore since it changes the "You're listening on" from "This Computer" to a Firefox Browser all the time. But it doesn't stop there because then it starts to play music from artists I've never heard of and skips through like 40 songs in 10 seconds. After that I can switch back to "This computer" and my recently-played-section is filled with random music. If I try to go back to normal I can listen to my music for half a song or so before its starting all over again.

What is going on here?!

I restarted my computer and router, I logged off from all devices and only signed back in on my desktop, I changed my password, I reinstalled the app and now I'm out of ideas.

Did someone else witness the spotify app gaining its own life?