Sound Input Too Loud... suggestions, please?

I initially asked about this last Summer, but I'm still having problems, so I thought I'd try again.

I'm trying to transfer some tapes onto CD-R before they're gone, and I'm having trouble with the volume of the inputs.

I'm using a standard RCA out (from the back of the DAT deck) to mini in (on the Apple) - but the input is too loud. Not terribly - but enough to distort the music on loud passages.

I've gone into the sound preferences, and tried adjusting the input volume there, but even with the slider all the way down I'm still hearing sound (which doesn't seem right). I've gone into the midi settings window as well, and the input levels are all the way down there - again, too loud. I've tried using the Griffin iMic USB... same thing.

The ONLY solution I've found is to take the output from the tape recorder and run it into a preamp, then take the output of the preamp and send it to the computer. This works fine, but I'd rather not add this other piece of equipment to the chain if I don't have to. I can go with this solution - but I have a feeling that people out there are plugging tape decks into the Apple all the time without problem, and I'd love to know why my situation is somehow different.