I absolutely stand to be corrected but, I don't think the little pokey hole is the microphone, I think it's behind one of the little grills pictured. Just checked mine and the hole and grills are the same as the picture, albeit black!
I had the same problem on my 09 car and did some tests, as I have in the new one viz: leaning over to the left and talking, apparently I was clearer. I also 'scratched' both grills with my nail and apparently the noise made was louder on the left grill.
When we had this problem originally I'm sure someone clever had a look behind the plastic and confirmed the microphone was there...on the left.