My LACIE hard drive shows up on some computers but not all.

Dear Apple Community
I need your help, as I have searched around and can't find a solution to my peculiar problem.

I have a 500gb LACIE Rugged hard drive product ID. RUG FWSA

It has these connections: firewire 800, firewire 400, mini-usb, power

I have always connected it via firewire 800 or mini-usb as my Macbook Pro only has a firewire 800 port / usb port, and firewire 800 is faster than the other options provided / I assume it provides the most power to the drive thus being the healthiest?

Now for the past while it has only shown up on certain computers. I have a mac G4 tower that it will show up on when I connect via firewire800

But it will not show up on my macbook pro that I normally use it on, and it won't show up in disk utility.

When I connect it to the G4 however it shows up both as a writable drive and in disk utility so I have been able to format it in to various partition styles to coax it in to showing up. It still doesn't show up.

Basically

500gb LaCie Rugged external HDD, ID RUG FWSA

Shows up on G4, both disk utility and writable

Does not show up on macbook pro anywhere

When connected to the macbook pro I can hear it and feel it turning on and staying on.

What have I tried already?

-Reformatting

-connecting it with a power cord attached, which makes me think its not a power issue, but I could be wrong

-connecting it and waiting for ages for the drive to show up in disk utility.

-the problem is not with the cord or 800 port on the hdd as it works on another computer

-the problem is not with the 800 port on my macbook pro as other 800 devices work on my laptop.

Any ideas anybody?

Is this a job for apple genius bar?