1D classic and speedlite problem, please help.

Hi. I've got a 1D classic and when I try to use it with a flash (550ex or 430ex) in M mode, or any other mode, the shots come out too dark. It doesn't matter what my shutter speed, aperture, or ISO are. Always too dark. It's as if the camera adjusts for these settings to get the image too dark. These flashes work fine on my 1dmk2 and 30d.

Is there a setting on the flash or camera that I need to change? Or just bad connections on the 1d?

Thanks.

It should work as per other cameras that you have tried it on.
I think it will synchronize up to 1/500, thats the only thing that different to your other cameras.