Assuming your TV isn't smart & has the BT Sport app, maybe look at another HDMI "stick" type device that supports the app directly. I believe Roku, Now & Amazon Fire would all do the job & not break the bank.
You can close this issue if you wish. I didn't want not to be able to watch BT Sport until some indeterminate date in January, so I popped out to Argos and bought the latest generation Chromecast device.
I wish that I had done this before now because I have downloaded BT Sport onto it and can now watch without the need to cast from my mobile phone.
If you do decide to investigate further and are able to solve the issue, I would be interested to hear what the solution was.
Cheers and Happy Christmas.
Thanks for the update @JJ49 - you're lucky that Google recently released an update for that device that fixed known big issues with it, otherwise you may have been disappointed with that too.
Glad it's sorted for you now.
Im also having the same issues with the 1st Gen Chromecast when trying to cast BT Sport and Discovery+ from an Android device. Casting from the same Android device to a 3rd Gen Chromecast works without issue for both apps. Casting BT Sport to the 1st Gen Chromecast from an iOS device also works fine but not Discovery+.
For the avoidance of doubt, casting other apps to the 1st Gen Chromecast is working fine so not an issue with the hardware.
Are you able to provide an update on when this issue is likely to be resolved?
Thanks for the extra detail @CaptainAmazo - it's interesting to know that Discovery+ is also affected.
When casting BT Sport from Android, it uses Google's latest SDK and player. When casting BT Sport from iOS, it currently uses their legacy player (this is scheduled to update in January).
I'll be home from my holiday on January 3rd. I'll check the issue straight away, and hopefully have a fix out that day - assuming it's something I can fix.
Exactly the same issue. Samsung s20fe, 1st gen chromecast had been working fine until recent weeks. Have re-installed BT Sports App & Google home repeatedly. Can happily cast my phone screen, & other apps like youtube. However I try with my phone, I just get the revolving wheel for a minute & otherwise blank screen. Meanwhile the action continues to be shown on the phone screen. Google Home seems to think it is casting & I have to "stop casting" to return to the ambient screen. I have been reliant on someone being present with an iphone for whom casting BT Sports to the same dongle works, but have now got an Amazon Firestick to use instead.
I would love to know if a solution is developed.