I've had an issue identicle to the one here
I would log in to the web player and noticed that there was already another browser session logged in somewhere else (under Chrome). My playlist would skip songs and often ended up playing songs by "Zae Day" or "Stack Up Gang," both artists I'd never heard of. I thought that my issue was unique until I found the above post, and noticed that they also had "Zae Day" showing up on their spotify as well. I solved the issue by logging out of all devices and changing my password.
I wanted to make the team aware that something is/was definitely up. Maybe my account got compromised and that's it.