Since the Stream Magic 6 V1 was discontinued, Spotify have changed the way their service can be used and the Stream Magic 6 can no longer support it.
Although it is still recognised as an available device, the Stream Magic 6 requires a manual login which Spotify no longer permit. Instead, you will need to use the Spotify Connect service.
First, you have to make sure you have a Spotify premium account so you are able to make use of Spotify Connect.
This enables you to stream connect wirelessly from the Spotify App straight to your Stream Magic 6. Please note you do not need to log in on the Stream Magic 6.
To play Spotify content on your Stream Magic 6, please follow these steps:
1. When your device and the Stream Magic 6 are connected to the same network, open the Spotify App on your phone/tablet/laptop and select your desired media.
2. Connect to the Stream Magic 6 using the Spotify 'speaker'/'Spotify Connect' icon.
3. Select the Stream Magic 6 from the list of devices (The image shows an NP30, but you will see the Stream Magic 6).
4. Once the Stream Magic 6 has been selected, Spotify should begin playing from the Stream Magic 6.
For more information regarding how to use Spotify Connect, please follow this article here:
https://support.spotify.com/us/listen_everywhere/supported_connection_types/spotify-connect/