Have to convert negatives twice to get accurate colour

The first time converting a negative or group of negatives I get weird colours. I have to unconvert and then convert again for the colours to be rendered correctly. Seems like a glitch. Anyone else have this?

Below examples. Brighter highlighted image 1st conversion. Then uncovert and convert again renders better. Would only allow me to upload 1 image so uploaded the bad one.

I’ve experienced this after importing and batch converting a bunch of scans. Doesn’t happen with every picture but sometimes I’ll have a few that have that thin, low contrast, light look to them. Unconverting and converting again always solves it.