I have a 21'' Sony CRT TV, model KV21M3E bought in 1999. Some years ago I managed to enter the Service Menu by pressing INFO, 5, VOL+, [ ] in the remote and adjust some geometry settings.
However, today I have tried again to access the menu and change some settings (due to a console that misses an important part of the top screen through RGB), and for some reason I can't change the parameters. As far as I recall I'm doing the same things as so many years ago, but it just doesn't work.
When I enter the code in the remote, the letters S RA TT-- appear on the screen. Pressing MENU in the remote brings a menu with "adjust" among other options. By pressing the directional keys on the remote UP (green) or DOWN (yellow), I can navigate up or down. Pressing LEFT (red) or RIGHT (yellow) on adjust, the geometry options appear and I can navigate them up and down, but I can't change them. Pressing left or right doesn't do anything, nor does any othe button on the remote or TV. I'm quite sure I didn't have such a problem the last time I did this, and I managed to change the parameters by pressing left or right.
Does somebody know what could be happening? I find this very odd. Thanks!