It's a Sony DVP-NS430 CD/DVD Player, connected via scart to a panasonic TX-50A300B tv.
But when I press AV on the TV's remote, scart doesn't appear as on of the source options, the list only includes:
1. Side AV
2. HDMI 1
3. HDMI 2
and that is it.
Just tried connecting DVD player via side AV jacks, and all I get is a constant buzz noise, and no picture.
Why does the scart input (back of tv) not appear on the AV source list?
Indeed, the scart (EXT 1) Source input was disabled in the tv menu, I have now enabled it and have a picture and sound from the DVD player.
Lesson learned - check the Basics!
Thanks for your help Shahid