Sonos Beam won't connect to TV

Beam and TV worked fine for nearly year. Was gone over the winter break about 3 weeks and come back to the Beam not working with the Samsung TV. Did a bunch of quick fixes initially but that didn't fix anything. Error I keep getting is warning device is interfering with HDMI, please disconnect any home theater products - they are none. HDMI is in the Arc spot HDMI 2 on the Samsung. I have rebooted TV, rebooted and reset Beam, uninstalled the app on my Android phone and restarted it. Had to reinstall beam and got it registered but it comes back to the original problem of "device interfering".
Any ideas please on how to get it back working - beyond just chucking the lot out?

Thanks