Print slows down drastically after the first layer.

[helter 0]

So, I tried to print something the other day, and ran into this problem. I started a 5 hour print, waited for the brim to finish and the first layer to start then left. When I came back maybe two hours later, the print had barely advanced from where I left, and appeared to be processing single moves every few seconds. So the head would move a tiny bit, wait, then move a tiny bit.

When I checked the Term screen, this is what I saw.

I'm using an Arduino Mega, with Marlin firmware, printing through a USB cable. I've printed quite a few things with pronterface/slic3r and didn't have this issue, so I'm hoping it's just something with my Cura setup.

Thanks!

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