how do i unlock my bravia sony tv 46 inches?

I've found 2 support alerts about the Travia line:
http://esupport.sony.com/CA/p/support-info.pl?info_id=1381
https://corporate.sony.ca/view/oct11.htm

It's plausible that you may be affected by one of those.

It's possible that that person accidently changed the video source. Consult yopur user manual to find how to set it back to the correct source.

You can find the manuals in PDF format here:
http://esupport.sony.com/CA/p/select-system.pl?DIRECTOR=DOCS
(without the exact model number, i can't go farther)

Electro
April 2014