Ok so the set up is a USB conector from my laptop to a mixer. If I do line in from my amp through the mixer the sound for the guitar, durring play back, is fine. but whenever I try to use a mic to pick up the guitar from the speaker (the mic is pluged into the mixer also), the play back from the guitar has this computerized disintigrating sound. whats the deal?
First, you're using Audacity which is a huge problem. Go get Reaper or GTFO

Second, ditch the mixer and go buy an audio interface

Third, what Mic are you using?
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