Hi there, 

I use Chromecast Audio to stream music from my Windows laptop and my Android mobile phone to my home cinema theatre. This usually works fine. However, I have encountered one problem: I cannot stream local files (from laptop and phone) that are in my Spotify playlists to my Chromecast Audio. 

When I play my playlists on my headphones, car of whatever other music output medium, the local files are being played normally. Also, I can stream my local files over Chromecast Audio through other apps on my phone, such as LocalCast. There, my conclusion is that there is nothing wrong with the local files, or with the compatibility between those local files and my Chromecast. 

I use updated versions of Spotify on my laptop and mobile phone. 

So, the only problem seems to be to stream the local files through Spotify to my Chromecast Audio. 

Is this a known problem? And how can I solve this?

Thanks for your help!