Hi there
There are a few things you can try before contacting Support (of which they will get you to do anyway)
- Disconnect the BT box completely from the TV (lets remove a possibility)
- Ensure that you have the latest firmware installed. See : HERE for more details.
- Perform a Factory Reset of the TV. Instructions : HERE
If things still do not work after that, there is probably not much this forum can help you with. Best to contact Sony Support : HERE
Let us know how you get on anyway - im curious to know 
Cheers
