Sonos Beam Gen1 and eARC with TCL 55P638K

Hi, I just changed my Sonos Beam from a Samsung TV ( sorry forget the model ) where the Beam worked seamlessly in that I could use Alexa to adjust volume on the TV etc. I moved the Beam to another property on a TCL 55P638K that has eARC. When I connect in the HDMI cable to the eARC port on the TV and then into the Beam and try to do the setup in the app it is telling me it doesn’t see a connection to an eARC port. I did a full reset of the Beam a couple of times and have also tried a Firestick in the eARC port and it is at least showing the pic and TV sound. 

The cable is the same cable I was using at the other property so I suspect it is not a cable issue although I do need to validate that. That said I’m fairly certain that is not the issue as I literally moved from one location to the other. Any suggestions welcome before I purchase the optical cable to HDMI adaptor and try that method ?

Thanks,

Dave.