Hi chansend
You have three options and two (IMO) are better than routing TV volume through a Connect:
The first as has been suggested is to connect your TV directly to the receiver.
If HDMI just use the receivers remote to adjust the volume or purchase a Universal remote that will also allow you to change channels if OTA; or if programed to a operate a cable box.
The second is to connect your TV to your receiver via optical or RCA cable.
If optical you may have to use the receivers remote to adjust the volume or purchase a Universal remote that will also allow you to change channels OTA; or if programed to a operate a cable box.
If RCA you may able to select variable out in your TV's menu. You would then set the volume on the receiver to a level just slightly above comfortable listening level. You'd use your TV's remote to adjust volume and change channels OTA or if programed to a operate a cable box.
The third is to connect your TV Line-out to line-in on the Connect (set to auto) and Line-out from Connect to Line-in on receiver.
Select the Connect as source on the receiver. Set the volume on the receiver to a level just slightly above comfortable listening level. Control volume via the Sonos App.
Cheers!
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