Can't launch Chromecast Spotify from my phone to my TV

[Leah63]

Plan

Premium

Country

Australia

Device

Pixel 2

Operating System

Android 10

My Question or Issue

Hi all, about a week ago the Spotify app on my phone stopped chromecasting to my TV. When I go into my 'Connect to a device' list on the app, my TV is listed as 'unavailable for listening'.

My Spotify app appears up to date (version 8.5.57.1164), I'm using a chromecast 1st gen with firmware version 1.36.159268. I have restarted my phone, uninstalled spotify and reinstalled, restarted the chromecast, nothing has helped.

At first I wondered if it was a bug in the chromecast firmware because it's a preview version, but my husband's phone chromecasts Spotify with no problems. Other apps on my phone (eg. youtube, netflix) all chromecast with no problems. I have discovered that if I open Spotify in Chrome on my laptop I can chromecast via the 'Google cast' option (ie, casting that tab) but the TV device listing is showing as 'unavailable for control'. Once chromecasting via the 'google cast' option, the app on my phone recognises Spotify is chromecasting and I can control everything from the phone app (eg. volume, track selection etc). I just can't launch chromecasting from the phone. 

The attached image shows the device listing on the web version of Spotify where the TV is listed as 'unavailable for control' but on the phone app it's listed as 'unavailable for listening'. 

Any ideas?? Thanks!