I was going to use Origin Valet for this project but the in-wall echo dot kp wont be released in time and using the in-ceiling version is a deal killer on this one. I do however want to maintain local source takeover at three locations with TVs. Basically I want the line input to take over the bus input for that zone when a signal is sensed.
Prefer a 16 ch zone amp with local source sensing.

what have you got?