Brownstain

This is an old post but I thought I would give my two cents. It looks like the filament simply is not getting fed through at a consistent rate or maybe the nozzle is clogged. I use an ANET A8. This is exactly how my prints looked when I had replaced the hollow screw that guides the filament to the nozzle. I realized I simply had that screw in upside down. After I flipped it, it worked great. The size that has the plastic part showing in the screw needs to face downwards and the beveled metal end of the screw needs to face upwards.