My PC's mobo has a Realtek ALC883 sound card with a header for a front audio panel. I bought a front panel unit that has headphone and microphone jacks along with USB and Firewire jacks. There were 2 plugs from the audio panel, one Azalia and one AC 97. The mobo manual is pretty clear on the ALC883 being Azalia so that's the one I used.

Everything works but the sound through headphones sounds like AM radio. The same headphones sound great with an iPod so I don't think that's the problem. I've installed the latest sound driver and adjusted all the relevant settings I can find.

Any suggestions?