External hard drive not mouting on my mac

Hi and welcome to FixYa,

Sorry to be the one bringing you the bad news but any sound from a hard drive is an indication of mechanical problem, often the head hitting the stops or bouncing off the platters.

Of course the recovery specialists would be a good idea. However, you may want to get a quote first and time required for the recovery. In some instances, the cost/time would no longer justify the recovery as an economical option.

Good luck and Thank you for using FixYa.

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