Can you replace the microphone in my LG Watch Urbane 2nd Edition LTE?

I recently purchased an LG Watch Urbane 2nd Edition LTE from the US in anticipation of the Android Wear 2.0 Update. It finally came through & I had a new favourite watch!

Then, this week, all of a sudden the microphone stopped working? There was nothing that preceded it, it wasn't dropped or knocked or anything, I just went to use Google Assistant to send a message as I had done 2 or 3 times prior on that day & it wasn't picking up my speech? I just thought it might have had some dirt in it obstructing the microphone port but when I inspected it, it was clean as a whistle?

Multiple Factory Resets later & I have determined it is a hardware issue & not a software issue so I was wondering how much I would be looking at to have the microphone replaced?

As I said, this is my favourite watch so it is quite precious to me so I would love to have it repaired if it is possible?