spotify 2015 update

[crawsail]

Hello,

I have Spotify Premium and I am using (2) Apple computers and an iPhone.

When I downloaded Spotify onto the 1st computer (a 2010 MacBook Pro), the 2015 version of Spotify downloaded and was I able to select "High Quality Streaming" (320 kbps).

When I downloading Spotify onto the second computer (a 2013 iMac Desktop), I've only been able to download the 2014 version of Spotify.

Although I can select higher quality streaming, I don't believe it is 320 kbps, as the sound quality is not as good as the MacBook Pro or my iPhone.

I have used the same headphones and played the same song, the sound quality is not the same.

Can someone please tell why I cannot seem to download the latest version of Spotify (2015) onto the second computer, and if it is possible how do I do it?

Regards