Trying to record from line-in

I'm trying to record an audio tape to my computer.

I have a stereo with a tape deck, with a stereo audio cable running from it to the blue line-in jack in my soundcard (an SB Live!). In Windows' sound properties, I've selected "Line In" as the recording source, but when I start up CoolEdit and try to record the tape as it's playing, nothing is recorded. I've used my own common sense and then followed directions online to set this up properly, so I'm not exactly sure why it's not recording right.

(Everything else works fine-- I usually have the stereo hooked up to the line-out so they act as my computer speakers, and I'm able to record "what u hear" in the sound properties, like off a website or whatnot.)

Any ideas?

m19