How to stop sony demo mode - Sony KDL 40CX520 40 CX520 Series Full HD BRAVIA Multi System LCD TV

I don't have a Sony HCDX1, so if this doesn't work, please do not rate me down.

Push the PLAY and STOP buttons (at the same time) and hold them for about ten seconds. This should get you out of DEMO mode.

Power the unit off, then back on. If the display now says LOCKED, then press the PLAY and STOP buttons (at the same time) again to unlock.

If this does work, please rate it Solved, so others can use this solution. Thanks!

Set the function to DVD. Press and hold the Stop and the Eject for 5 seconds and unlocked will be displayed and then eject. I just did it. Yipeee!

Had the same problem. The display of the home cinema system kept showing "sony demo". I went to the system menu and reset all settings to factory!

You need to turn off the DEMO mode. It's on page 10 of the manual:
http://www.xplodsony.com/files/manuals/CDX-GT310_Owners_Manual.pdf

Push the play and stop buttons simultaneously and hold them for about ten seconds. This will get you out of demo mode.

while the demo is playing you must press "Play"and "Stop" buttons, then display shows DEMO OFF and you can now take the DEMO CD out.
In some models you need to turn off the power and turn it on while pressing the EJECT Butoom.
SONY SPECIALIST