I < may > have a defective cable. I trimmed the small end that goes into the Surface and as I was trimming it, the entire cover came loose and slides back up the cable.
That eliminates any problem plugging it in
But, it seems to go in either way. One way looks to be a little further in that the other way.
There is a small piece of black plastic that I was wondering if there was a plug in the hole and if I need to remove it.
I went into Display on the Surface and found the Project to a Monitor spot and told it to Duplicate the display on the second monitor but I get nothing.
Monitor says no HDMI signal.
< sigh > looks like I spent $8 for a screen wiper and another stylus because apparently this cable doesn't work.
It was advertised as for the Surface Pro so it < should > have fit without even any trimming.
Without the casing it certainly has no problem going in until it hits something and won't go further.
When plugged into the monitor and the Surface Port, the monitor is not listed under Devices and Printers either.
I just got one of the docks yesterday and it came right up. I originally tried a generic monoprice adapter but with the side of the surface being at an angle, I couldnt get that cable to properly seat. I now have the dock and the official surface cable. you can try swiping the right of the screen and choose devices. you should be able to control which monitor you want from there but like I said, mine came up straight away with the dock and MS cable in mirrored mode.