Stereo Audio Output Inverted on Realtek Front Panel and Firewire Card

Hi,
I just realized that stereo output is inverted (L&R are swapped) on my Realtek front panel headphones connector and on my M-Audio Firewire card. Output is OK on Realtek rear main/front speakers connector.
Any ideas on how to fix this?
Thanks,
J

The front panel Headphone switch could just be a wiring error in the front panel, since it is correct at the rear panel. Or the cable that connects the front panel to the motherboard has a wiring error (assuming the connector is properly connected). Many cases have two audio connectors for the front panel, HD Audio and AC97 audio. The HD Audio is the preferred, if you are not using that, connect it and see if that helps. If you have HD Audio connected, and you have AC97, use that.

The MAudio device is a separate issue. I have a Sonar X2 recording studio and have an MAudio Fastrack Ultra 8R interface unit (and a Roland Octa-Capture). I used to have a firewire unit, a Focusrite Saffire Pro 40 and any channel swapping was done in the DAW program (e.g. Sonar).