AG8 front pannel sound, firewire, and ambulance noise

Thanks to anyone who can help me, this is my first time building a
computer from scratch like this, so it's taken me a while to get
where I am now.

I have an Abit AG8 MoBo, and it has onboard sound. I'd like to make
use of the headphone jack and mic jack on the front of my case, and
still be able to use the connections from the back of the case that
come with the mobo.

Can I even do this? how? what jumper combination should I use?

Also I hooked up the front pannel USB ports just fine, but the
firewire connections on the mobo have more pins than the
connectectors on the cable comming from the front of the case. I'm
missing the 3rd ground, +12v, and -12v. instead of those three, I
just have a vcc. (I hope that makes sense. can I still have front
pannel firewire?

Also, I used to have a problem where I got the 8.3 post code, then
nothing happened, but I figured out that I had a short on the 4 pin
power on the mobo. Now it sort of works, but I get an ambulance noise
of beeps (long short long short long short). I'm pretty sure this is
because I don't have anything (no hard drives, disk drives, or video
card) hooked up. but if anyone else knows something I don't, please
let me know.

Thanks very much for all your help.