Multiple recorded tracks don't sync up...

I have been trying to record one guitar riff into audacity through my Line 6 POD X3 Live (USB input) I have no problem recording directly into Audacity, however… when I try and record a second track in parallel with the first, I play in time with what I hear played back, however… the tracks do not sync up during playback of both tracks. Is this an issue with system memory? Buffer length? input type? I just want to be able to record a full song all on my own track by track… without having to sync up the timing on my own. Thanks in advance -J

In the Edit menu, select “Preferences” and on the “Audio I/O” tab switch off “Software playthrough”.