Projector P1273 USB mini port -- is it a signal source? Brand new projector, just learning to use it. The manual, page 7, for button 22 on the diagram, which is the 0 key on the remote's keypad, says "Press USB B to change source to mini USB (USB 
." But it doesn't seem to work. When pressed, I see in the projected image a small red circle with a diagonal line through it on top of an image of the remote control. I assume this icon indicates to me that the button is not an option. But why have two separate buttons for USB A source and USB B source (key 7 and key 0, respectively)? I strongly suspect the manual was written wrong. These two source buttons are for the two full USB ports on some other model in the series. Tech writer got confused. But I am seeking confirmation. I contacted Tech support via chat and they said there was a hardware issue, want me to mail it to a service facility. But I am doubtful. I think they just read the manual, too, during the chat. Can any other users please confirm how this button works for their projector? All I can do with the USB mini connection is page up and page down via the remote when in a Powerpoint presentation using those other buttons also found on the remote. Thanks.
