Review on 🕹️ PORTTA 4x2 HDMI Matrix Switch: 4K@30Hz, Full HD 1080P, 3D Support, with SPDIF Coaxial Audio Extractor and IR Remote Control by Greg Baker

This switch does not break all HDMI lines between the outputs; Either that or it has some sort of internal matching circuitry that doesn't renegotiate the input port or when switching. This means that your input system will only recognize one of your two outputs (as a connected device) and may not be the one selected. This. You have connected a 1920x1200 display and a 1920x1080 projector as outputs. Even if the selected output is a projector, the input system (PC in my case) sees the display; and cannot set the screen resolution correctly - the projector is receiving a 1920x1200 signal. It is then necessary to disconnect the monitor from the box, disconnect the PC from the box and reconnect the PC - only then will the PC recognize the projector instead of another output and be able to use the correct resolutions. This defeats the purpose of the device and renders it useless. It's not a big problem if both outputs use the same native resolution, but you might still have some problems, e.g. the color profile is not applied correctly or other output-specific settings; 3D won't work if one of your outputs doesn't support it. I was expecting a more robust solution where all HDMI pins are connected/disconnected between their respective inputs and outputs. Further research has shown that this problem can be caused by the lack of an EDID. Control on this box - most likely writes / skips the first EDID information it gets from the connected output; this means that the 2 outputs must be very close/identical in their supported resolutions/modes and identical in their native resolution. I messaged the seller about this, we'll see what they say.