Can't get rid of PS4-946 device on my account

[denNorske]

 Hello!

I have a premium spotify account, and i have 3 devices only that is logged in to my account.

However, last night I discovered something disturbing. I was going to change to my device in the living-room when suddenly I got my eyes on a device named PS4-946 --> which could probably appear to be a PlayStation 4 unit. 

But I never shared my password (pretty safe one) and as I said, I only have 3-4 devices i Use. 1-2 Phones/tablets and 2 PC's.

I tried logging out from all devices from my account on Internet, also changing password 3-4 times. But none of those solutions work, as the device is constantly popping up at the list.

It never stole the music from me, and it's not offline either.

What can I do? And who/what is doing this?

(please note, i do not have an PS4 or know anyone who has it.)

Here is a screen-capture of the name: