Spotify connection request times out from iPhone (9.1)

[FramlRR]

When trying to connect to both Chromecast Audio, and regular Chromecast  plugged into my tv (2nd gen) Spotify does not connect. Spotify does recognize that I can stream to both Chromecast devices, and sends the signal to connect (Audio bleeps and TV switches to Spotify app). However, after this point the app keeps trying to connect (without ever fully connecting) until the connection request times out.

I have re-installed Spotify on my phone and re-booted both my phone and both Chromecast devices without success. 

Also good to know, I can stream to both Audio and Video via Rdio from my phone without a problem.

Anyone any idea what can be causing the problem? 

Help much appreciated, as Spotify is my 1# use of the Chromecast.

Thanks,

Frank