[linux-audio-user] Problem with audacity

Hi As everyone recommended, I am getting my son to use audacity, but now we are having a probolem where secind track becomes very noisy after recording. The first track records fine but when the second track is recorded it is very noisy, and even seems to have a pitch shift. When I tried to figure out what is going on I found out thet the first track is bleeding through to the second track. So even if I mute the second track when I record the second track I see the first track bleeding through and see the waveform on the second track. Please keep in mind that the input is a guitar pickup not a mic so there should not be any crosstalk between tracks. I am using SB live with alsa-0.9.4 linux-2.4.21 (lowlat) audacity-1.1.3-1. Anyone seen this before?? Regards