Just tried it with them disconnected, still the same. I think it is a genuine VGA addapter.
It's weird as it did work. First it wasn't working, not giving me the options for analog. I thought it might be that the analog option would only work if an input was plugged in, connected up my SP808 to the input, and it was working, so i thought that it was now cool. But now it is not working again even with an input source plugged in. Tried a bit of contact cleaner in the Jack sockets, no joy!