Internal Samsung hard drive issues

Hey guys,

Spent hours in the last couple of weeks trying to find info on what the problem might be, but there's very little out there and Samsung have merged their hard drive support with Seagate, the Seagate site is no help whatsoever!

Samsung HD642JJ

Anyways I've had this drive for about 18 months (the warranty checker shows that it doesn't qualify for an RMA, pity) and about 2 months ago the write and read speeds dropped significantly during transfers, read speed averages about 11MB/sec, write speed averages about 3MB/sec. Also if I was viewing a video file when the transfer (read/write) started the video would stop for a minute or two and then start to lag and stutter. About 2 weeks ago a clicking started coming from the drive every now and then, again if I was watching a movie or anything it would stop, wait a few minutes and the click would be heard again and the movie would come back perfectly. I've downloaded a host of tools, most probably do the exact same thing but worth a try, all the tools find no issues at all with the drive. Just to be safe I've purchased an external drive to transfer all the data over, it finished successfully but again with very slow transfer speeds and this persistent click would pause the transfer now and again.

I've checked the firmware and it has the most up to date one available. I've checked drive, the cables are fine and the drive is docked ok. I'm guessing the click is the best indicator of what may be up with it, but as I've said the tests all come back perfect. It passes SMART, short generic tests and long, HD Sentinal gives the message - "The hard disk status is PERFECT. Problematic or weak sectors were not found and there are no spin up or data transfer errors. No actions needed." Funny thing is that during all the tests the click can be heard, the test will stall for a few minutes but once resumed will give a perfect result.

Hopefully someone can give me some clarification on this, I'm pretty sure that this drive is weeks away from a complete failure but the diagnostics software is saying otherwise! And if the drive is still usable I'd like to get the transfer speeds to a reasonable level.

Thanks for your time guys, any help at all would be much appreciated....