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The pop might be the blowing of an internal fuse.
If the fuse blew because you have run the Sharp CD Player directly from an outlet, then you can prevent this sort of loss of electronic device function, to a great extent, by investing in a surge protector to power every electronic device of any value in the house. A surge protector is an investment that always pays off in the long run.
As for repair to this Sharp device... there are various Sharp repair facilities and shops in various regions. If you let me know your local zip code, or town/city and state, then I will list for you all local shops that you might take the Sharp device to for repairs.