I've connected the front panel audio up on my AB9 Pro (I think) and indeed the audio out works as I've connected headphones to it.
But I can't get the microphone to work (it does work in the rear connector). I've checked in the mixer that "pink front panel" is not muted or with very low level.
Also, I notice that when I plug into the rear connectors it detects and I get a little notification in the system tray and a pop up window checking what I've plugged in. Also, in the Realtek HD audio utility it highlights the device now plugged in. But I get non of this with the front panel audio.
It also looks (may be unrelated) that the digital audio in/out are active (seem highlighted as well) although I'm not using any digital audio in or out.
Do your front panel connectors work just as per the rear ones?
Andy