Check the following settings to correct this issue:
1. If the source gives the correct 3D information to projector, projector will
switch to 3D automatically.
If your source is from PC or steaming content, please select the correct 3D
format via OSD Display > 3D > 3D mode.
2. Check the user manual and make sure that the resolution of your content supports 3D.
3. Press the DLP Link button on your 3D glasses to resync the projector and 3D glasses.
4. Please try to change HDMI EDID setting to Standard.
If the problem persists, please contact your local BenQ service center for more assistance with the following information.
• How devices and projector are connected
• Mode number of video source device
• Cable length and material
• 3D format from input source
• Media platform of input source
• Firmware version running on the projector