[LAU] Elementary help needed with qTractor

Several years ago I managed to produce some multi-track midi files using qTractor. Now I want to do something fairly simple using audio tracks.  Just to get myself back into using qTractor after a very long break, and to find out how to do what I want, I decided to try something very simple to start with.  I want to record a guide track using my voice, and then record 3 other voice tracks (separately), listening to the guide track through an earpiece.  Then I shall delete the guide track and experiment with altering the pan settings on two of the other 3 tracks to see if I can get a good stereo effect.  I'm using an HP laptop and its internal microphone, with an earpiece plugged into the computer's headphone socket; no sound comes from the computer's speakers, of course. Recording the guide track is no problem.  To record the second track, I set it up as an unmonitored audio track and set the guide track to solo.  I then record the new track whilst listening to the guide track through the earpiece. But after recording the second track, even if I delete the guide track, I can still faintly hear what was on the guide track - in other words, the new track has recorded the contents of the guide track at the same time as the new input from the microphone.  I have tried this several times, and I can't figure out what I'm doing wrong - probably because I'm a musician and not a sound engineer. If anyone has the patience to try to steer me though this, I shall be extremely grateful. David