When it comes to HDD/External HDD. If there an issue with the head reader or any clicking or any other irregular sounds, the HDD is pretty much done and cannot be repaired. Data recover also would be impossible. The way the PS4 creates its partitions on the HDD are not readable by a PC. only the PS4 can read them. Even if we could the data off it, there would nothing we could do with it. My suggest is just buy another external HDD. If you have a warranty on it, I would send it in to the manufacture and get them to send you a new one.
Not sure. They can advise you.
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