Recording Problems with GarageBand

My micophone makes bad noise only in GarageBand while recording. The record sounds bad, too. It crackles very loudly. That's a new situation for me. Until now everything works nice. There are no problems with other programms. I use a USB Audio Interface Line6 TonePort UX1 with an AKG C1000S microphone. Can you help me please. Thanks a lot. Sorry for my bad english.