alastairward,
You might want to try the device manager in your computer to see if you can see the drive information, and see if it's mounted and transferring information. The buzzing definitely doesn't sound good, and often times buzz or click noises signifies the end of a drive. If you are able to get it to connect, you may want to use that opportunity (if you can) to back up any valuable information on the drive.
Hope that helps.
--HDTech
For no apparent reason, when I switched on my Samsung HD160JJ, it started buzzing. The buzzing goes on for about ten seconds with a definite pattern; "bzz bzz bzz bzzbzz". It's installed in a caddy that plugs into my PC via a USB cable, the PC recognises that something has been plugged in but doesn't recognise the drive. Anything I can do before assuming it to be dead forever?

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