What you have to do is first establish a connection to the TV as an external display, as in you see your Mac desktop on the TV and your laptop recognizes that it is connected to a second display in System preferences > Displays. Don't worry about mirroring displays or running them independently at this point, you need to get to the point that the TV is merely recognized as a 2nd display. It's usually easier to do that for the first time by connecting directly to the TV rather than first going through an intermediate device (the AVR) as you are trying. Going through an AVR is possible, but it's rarely "plug and play" so the first thing I'd do is connect directly to the Bravia and see what happens.
Which model MBP do you have and what are you using to get HDMI out of your MBP?
Which model MBP do you have and what are you using to get HDMI out of your MBP?