Sound crackling and volume loss in recording in Audacity?

Whenever I try to record an instrument on my laptop the sound will be distorted and there will be crackling noise and after 10 seconds into the recording the volume drops and the sound quality is really bad. This never happened on my old pc that had windows xp, but whenever i try to record on my laptop with windows 7 it records crappy even with a good mic. Is it the soundcard?