Hi, I am trying to connect a microphone (cheap no-name $5 mic) to a DB-9 port. The mic i am using has a black and a red wire, i have tried connecting the wires to pins 5 and 9, 5 and 4, 9 and 4, what pins are the right ones? what does mic_vref mean? here is the pinout:

9-Pin D Connector (female)
Pin# Signal
5 MIC_VREF
4 G ND 3
3 LINE_IN_GND 5
2 GND 7
2 GND 9
9 MIC_IN 2
8 LINE_IN_LEFT 4
7 LINE_IN_RIGHT 6
6 OUTPUT_LEFT 8
1 OUTPUT_RIGHT 10