Essentially, an external hard disk consists of 2 parts: (1) the case including the electronics, and (2) the disk.
(1) If the case or the electronics is broken, buy a new one an transfer the disk. All will be fine.
(2) If the disk is broken contact (for example) www.drivesavers.com and ask for a quote. Then decide if your data is worth more than their bill will be.

An uncommon sound points to #2.

Kees