[quote=“strangely, post:10, topic:168617”]Just remember that things will also get interesting if you have HDMI CEC enabled on other devices (it may be by default on your TV’s etc) and you’ll find that if using an HDMI matrix switch, that the HDMI CEC messages will go across every HDMI cable and device on the matrix, and you can then have all sorts of things turning on and off 
The good thing is that these IR injectors also use the HDMI-CEC wire, and they serve to block the signal… This is actually the other reason why I wanted to use these as I’m using HDMI-CEC locally at each TV for my TVs and AV receivers!
Which Matrix switch are you using?[/quote]
I am using the Monoprice HDX-404E. Switch works really well, but unfortunately I cannot get the Sewell IR Injectors to work reliably and not interfere with the signal on my projector. I am probably pushing the limit of what can be done with the equipment I have as I have the basement all on one system in a media closet with Denon AVR-1912 running a Epson 8350 Projector, Monoprice Matrix switching XFinity and WD Live TV only currently and 2 other LCD TVs (Bar and Gym). I also have a ATON DLA4 and a separate Yamaha receiver for using in 4 zones with SQ Blaster hardwired to DLA4 for control.
Having a lot os reliability issues with setup, SQ Blaster needs to be reset periodically as it stops responding, and if I install the 3 Sewell IR Injectors in the 3 screen locations I cannot get 2 of them to repsoind at all and the Projector has image issues sometimes. Setup I cam currently using is only a single Sewell injector on the projector and a Harmony Remote in theater that does everything for that, and local remotes in bar and gym and SQ remote for switching inputs for those locations. SQ Remote also controls audio system.
Am probably in the end going to go with either Harmony 890 Pro, which will allow different room control, lighting and RF to closet, while providing local IR for Tvs and Projector.