Yup, either a driver over heating or a USB connection issue.  Add a fan on the board to cool the drivers.  If that doesn't work, then it is probably a USB issue.  Are you printing from a computer?  I know I have a fairly weak laptop, and sometimes if I do so much as start a youtube video while printing, the freezes up for a second then starts again.  The solution is to not ask so much of my computer, get a better computer, or add an SD card reader and print from that.  Or print from my tablet with the G-code printr app, which I do most of the time.

I too have a relatively old and weak laptop and even slicing fairly large or complex objects freezes the printer. I've just lived with it this whole time.

I am betting that it is a hardware issue - mine was doing the same thing, and it will get worse.

I had a bad usb connection, but I also suspect (now) that the stepper drivers were overheating as well.

Try getting a fan pointed directly at the controller board /stepper drivers to cool them better - the little 40mm one that SD uses on the bottom isnt enough.

I managed to point a small fan towards the board and it seems to do the trick. I might have to flesh out a more permanent solution to the problem though. Thanks for the tip mate!

I know I have a fairly weak laptop, and sometimes if I do so much as start a youtube video while printing, the freezes up for a second then starts again.

lol, yeah, i am running ours from an old XP machine & dont do anything else with it while printing or it starts having issues. LCD & SD card reader are on the upgrade list...

I had a bad usb connection, but I also suspect (now) that the stepper drivers were overheating as well.

Try getting a fan pointed directly at the controller board /stepper drivers to cool them better - the little 40mm one that SD uses on the bottom isnt enough.

Just recently, I've been printing pulley sleeves and it's been randomly stopping during prints. There is still plastic oozing out of the nozzle when it stops, but the extruder itself doesn't move, leaving a very small but inconvenient blob on the surface. Not even a second later, it resumes printing.

What would be the main cause of this as it has never happened before? I suspect it might be software issue and not a hardware issue.

During the print, I was printing black ABS on hairspray/kapton tape (210 deg C @ nozzle; 110 deg C @ heatbed)