I had the same thing going on and assumed it was my printhead. A few day later, I was running a test print to get a measurement of the position of the dropout so I could work around it and it had cleared up. That was several months ago and (knock wood) it has been fine ever since.
In my case, we had coincidentally just terminated the employee that had been running our Edge. When I examined the Edge, the first thing I noticed was that the shocks that hold up the lid were completely shot and the former employee had never told me. My guess is that he had allowed it to slam shut a few times with an intermittent connection ending up as the result. I replaced the shocks, remade every connector connection ... and all has been fine since then.
So, although, your symptoms sound like a bad printhead, my suggestion to you would be to unplug the machine, remove the covers and remake every connection you find while also giving it a good visual inspection. You may get lucky like I did.