<p>I am currently encountering a problem where under certain circumstances, the extruder stutters when it starts a new layer. I am printing on an Anycubic i3 Mega and am slicing with Cura 3.6.0. The problem seems to occur in the main part of prints, as well as in supports. However it seems to only occur after a retraction has taken place. I have taken a video of the stuttering which can be found here: <a href="https://photos.app.goo.gl/G3TLKveMsLNRQmgv7" rel="nofollow noreferrer">https://photos.app.goo.gl/G3TLKveMsLNRQmgv7</a>
When a print is done the stuttering results in walls looking like this:
<a href="https://i.stack.imgur.com/AlAZQ.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/AlAZQ.jpg" alt="In this case, the problem occured in the support structure"></a>
Can anyone help me figure out what is causing the stuttering?
Thank you very much!</p>

You retraction settings may be too high. Direct drive extruders require less retraction than Bowden style extruders. Typical retraction settings for direct drive are 1.5mm at 50mm/s and for Bowden, 4mm at 50mm/s. The speed usually makes more of a difference than distance beyond a certain point.
You can get away with smaller retraction settings if you increase travel speed because there will be less time to ooze. You could also try using Coasting as well.
Anyway, try reducing your retraction settings if they're higher than what I stated above. Another alternative is to set an extra prime distance so that extra filament is extruded after the retraction.