Here’s the interesting context around that seemingly simple link:
URL you shared ( soundcloud.com/activate ) returns a status. This typically means the page exists but is locked behind a login – you need to be signed into your SoundCloud account first before the server will show you the activation code entry screen.
SoundCloud uses that page as a device-linking gateway . When you open the SoundCloud app on a TV, game console, or smart speaker, it shows a short code. You’re supposed to visit soundcloud.com/activate on your phone or computer while logged in , enter that code, and pair the device.
The 401 error means you tried to visit the page – SoundCloud’s server refuses to show the code-entry form until it knows who you are (so it knows which account to pair the device to).