Inconsistent squiggly perimeters

I have a VCore 3.1 500. For the life of me I have not been able to narrow down the cause of this squiggly line that starts each perimeter. Direction of travel is black arrow. Squiggle circled in red, normal end of perimeter is circled blue. Acceleration and print speed values have not made a difference Phaetus hotend, bondtech BMG. Duet running reprap and linear advance is tuned!