When I have had a problem with this exact issue I have had some success with pushing play while the tray is open with the disc in it. Maybe it bypasses some form of detection, but it sometimes works.
Sony DVPS9000ES & Hybrid SACDs
ANYONE KNOW IF THERE ARE DIFFERENT VERSIONS OF THIS PLAYER WHERE SOME OF THEM WILL NOT DECODE SACD INFO FROM SACD HYBRID DISCS?