[NBLUG/talk] Recording phone calls directly to the sound card

[Robert Hayes]

I have an ongoing need to record telephone calls.

In the past I've simply used a small interface box from Radio Shack. 
One end goes into the RJ11, the other end is a monoraul mini plug that goes 
into a cassette recorder. There's also a small mini plug that will trigger 
the remote on/off feature of the recorder, but I've never used that.

I'm running Knoppix, 2.4.2 kernel on a system that does not have a modem, and 
I would like to avoid having to install one.

When I record to the cassette recorder, life's good.

When I take the headphone out from the cassette recorder to the line in on the 
soundcard, life's good.

But if I try to record directly to the sound card by connecting  the phone 
interface box to the sound card line or mic in, there's a huge amount of 
ongoing buzzing, and the sound quality is very low, and distant.

What am I missing? What am I doing wrong?

Thanks.