A couple of things to try - in the Alexa App you should see two icons for your Arc in its device list, one icon has a TV icon - select that and edit it’s name (see screenshot) to something unique, like ‘TV’ or ‘Prism TV’ and ask Alexa to scan for devices and then see if it works by including the name you gave the device in your voice instruction - eg. ‘ ’ and see if that works.

If the above doesn’t work for you, then there ‘might’ be a further option in your TV settings along the lines of ‘auto power on’ near to your HDMI-CEC settings that might need to be enabled, but you may need to check the TV settings, or the user manual to see if such an option exists. 

Thanks for your help Ken, I am using the Google Assistant instead of Alexa. I shall give it a try and see if it works. 

Ah I see (sorry, my mistake) but it’s a similar thing for Google VA too, you will see an icon for the TV control in the Google Home/Assistant Apps - simply give it a ‘nickname’ of ‘TV’, or ‘Prism TV’ etc. 

Interestingly when I called out “Hey Google”, both the TV and Arc’s assistant responded to me. Both are active and the TV’s assistant was able to turn on and off the TV if Arc’s Google Assistant ‘gets out of the way’ :) I have to find a way to speak directly to the correct Google Assistant to effect the correct function! This is a tricky situation! 

Perhaps just switch one of them off - simply tap mic button on the Arc to turn it off. I’m in a slightly different position in that I have to press a button on my TV remote to make the assistant wake up.

My TV’s assistant is eavesdropping all the time :) Although I have to use the remote control to activate the Google Assistant when it goes into ‘deep hibernation’ mode sometimes :) Indeed, that was what I have resorted to (disabling the ARC’s mic). However, I was unable to get the TV’s assistant to start Spotify or TuneIn until I have them installed on the Android TV.

The issue now is the TV will turned itself on to activate the Spotify and TuneIn services where I previously had the ARC streamed those music without turning the TV on. 

I guess you can’t have your cake and eat it. These are the limitations with the interconnectivity and protocols between the Google Assistants within ARC and the Prism+ TV. 

@tausing 

I’d personally just choose to change the Arc’s assistant to Alexa - that would quickly solve the issue. I use both assistants, as each service has their advantages. The Alexa auto-grouping/ungrouping of Sonos speakers is particularly useful for music playback around the Home.

Great suggestion Ken! I will try that out! Thanks for all your helpful advice! Cheers! 

It’s interesting that the Google assistant in the TV can’t be deactivated. I have Alex and Google assistant options for my LG but chose not to activate either. I have Sonos sound bars with Alex on all 4 of my TV’s. I can command Alex from any Sonos soundbar to turn on or off a TV in another room. For example from Bedroom I can control on/off for TV in living room and vice-versa.

Incidentally, I successfully turned on the TV and SONOS ARC in my Living Room using my SONOS Roam from a separate room. I was able to turn them off too with the Google Assistant. It is a new discovery for me. Thanks for your suggestions @AjTrek1 :) 

Using my SONOS Roam from a different room, I was able to switch on the TV and SONOS ARC in my Living Room. With the Google Assistant, I was able to turn them off as well. For me, it's a brand-new discovery. thank you for your suggestions.)

Ken, you make a fantastic proposal! I'll give it a go! Thank you for all of your valuable suggestions! Cheers!