First Layer

Aha, ok, I thought you were having issues with the line drizzled on the surface of the print in the direction of travel from the main object to a hole for example. You’re having issues with the actual layer thickness consistency itself. There are a couple things to try there, tighten the idler tensioner arm bolts slightly front and back, increase your printing temperature slightly, and potentially turn down the speed while you get things dialed in.