If it was one motor, I would say it's probably a bad ESC. But you have it on all four at the same time. Is it possible you have one ESC board that controls all four motors? I don't know. I'm not real familiar with the original Phantom.
Edit: Found this:
It seems to show each motor as its own ESC so that can't be the problem.
I would recommend sending the drone in for repair for the safety of flight.
Please fill in some info on our online repair link of our official web and then send it back if you need. Here is the link: https://repair.dji.com/en/SelfRepair/Area …
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