I found this in the manual:

Hints
The cable required to output a particular video mode may not be included with the product and additional purchases may be necessary. For details, refer to the documentation supplied with your system.
If the video output settings do not match those required for the TV in use, the screen may go blank when the resolution is changed. The screen should, however, automatically go back to its original resolution after a while. If the screen remains blank for more than 30 seconds, turn off the system. Then touch the power button on the system front for at least five seconds to turn the system on again. The video output settings will automatically be reset to the standard resolution. If a device that is not compatible with the HDCP (High-bandwidth Digital Content Protection) standard is connected to the system using an HDMI cable, video and/or audio cannot be output from the system.
Copyright-protected Blu-ray video discs can only output at 1080p using an HDMI cable connected to a device that is compatible with the HDCP standard.


This might explain the blank screen. Check the manual, it does seem to matter how it is set up and connected, but according to the manual it should revert to 480i. If not turn it off and back on - maybe?