Artifacts when transposing

I’m getting artifacts in Plini X when transposing my guitar. Just wondering if it’s normal or not, the first progression is -8st the second is -6st. It was recorded into garage band through a UR22C, nothing was peaking in the mix or in the audio interface. The guitar I used was my RS guitarworks custom Strat with Rio Grande pickups played in position 2 (middle and bridge).