I would check the settings of the TV (Bravia Sync). Look at the settings of "Control for HDMI" and "HDMI Device Selection".
Hey Da Flex, thanks for your comment, I have checked the Bravia Sync options, and the device does show up, but doesn't work when changing to the correct channel.
This started to happend after switch HDMI cable?
I know that you said that already tried with a new HDMI cable. So the only thing I have to say is check HDMI cable version, because only from 1.0 version works with CEC.
edjalmo, thanks for your comment.
No it started happening with the existing HDMI cable that was working, then I switched to a new one as a test.