The previous two replies ignore the SCART connector, which is an input socket.
You connect the SCART socket of your TV to the SCART socket on the DAV DZ20 (this assumes that the TV has a SCART socket which acts as an output). You should then be able to direct sound through this socket. (You'll have to consult your TV manual to see how to do this.) Page 20 of the manual explains this, but I suspect that it is designed to work with Sony TVs. It may, or may not, work with your Bush TV.