super Slow Ext. HDD out of the blue

[nks06]

Hey guys-

so all of a sudden my external hard drive is acting super slow... and it will happen in bursts. It'll act normal, then all of a sudden it'll slow down a ton. It's connected via firewire 400 and it is OS X extended (journaled). I did a test in Xbench and here's what came up:

Disk Test 52.87
Sequential 54.13
Uncached Write 56.41 34.63 MB/sec [4K blocks]
Uncached Write 54.02 30.56 MB/sec [256K blocks]
Uncached Read 41.60 12.17 MB/sec [4K blocks]
Uncached Read 73.47 36.92 MB/sec [256K blocks]
Random 51.66
Uncached Write 21.10 2.23 MB/sec [4K blocks]
Uncached Write 99.72 31.92 MB/sec [256K blocks]
Uncached Read 90.97 0.64 MB/sec [4K blocks]
Uncached Read 110.84 20.57 MB/sec [256K blocks]

does that look normal?

It's a Western Digital, and I'm wondering if that's my problem. I've been seeing a lot of WD crapping out on a lot of people...

Also, I used to used the drive on my old MacBook, but then I spilled water on it (last weed) and it died, so I'm borrowing my church's mac mini, and this just started happening in the past week.

Any help would be extremely appreciated =]