Removing background televison from recording

I have an audio recording in wave format of a face-to-face interview. Throughout the recording the television can be heard in the background, and at some points makes it very hard to hear my grandfather. I tried the noise filter, but even when the slider is set to low it tends to distort the voices, makes 'em sound like they’re underwater.

I ran Audacity’s analyzer on the noise, then tried to fit a FFT filter to the profile, but the range for the FFT is so large that I can’t adequately match the curve.

Yes, I’m very inexperienced with all this, so any pointers would be appreciated. Even if I can’t remove the background tv noise, I would like to be able to reduce its volume in the playback.

Were you using one microphone for the talk? If so, you have no show. All the noise and interference tools work on a stereo show, or an interfering noise that is constant through the show like an air conditioner, pump rumble, or power hum.

You can’t separate a mixed mono performance featuring two performers (granddad and the TV) into two different mono performances.