URGENT HELP! Snap, Crackle and Pop...Can't get rid of them!

[Emdee406]

Ok, here is my problem. From the moment I open Pro Tools 8.0.3, there is a loud crackling and popping in the headphones. When I hit record, it registers on the track, making recording impossible. I have tried on a Mac Book laptop as well as my iMac…same result. I have tried a different USB lead, same result. The set up has been running fine for over a year until now.
I AM using the same computer for everything, I know that a separate drive is recommended, but this hasn’t been a problem and at present I cannot afford one.
I have a Bluetooth keyboard and Track Pad, they have been used for at least 9 months with no issue.
I turned Airport off (normally always on) …no difference.
Basically I have changed NOTHING on the system , but now it is presently un-useable and I have urgent Voiceover work pending.
What I know about computers has basically come about in the last year, so don’t get too techy on me!

Computer model and processor speed – iMac G5
OS version – OSX 10.6.8
Digidesign or M-Audio hardware model – Mbox 2 Mini
Pro Tools version – 8.0.3
Amount of RAM installed – 1 GB 667 Mhz DDR2 SDRAM
Printer attached via USB.
Tried different ports, different computer…no change.
Tried everything in the Setup and General Troubleshooting thread as far as I can tell.
Any ideas? I’m desperate as I cannot work until I resolve this.

Thank you.

[TwoEdgedSword]

You said that you tried a different computer too? If you did, and the problem persists, I would think it's one of two things. The first would be that you were connected through a usb hub and not directly into the computer. If you are running directly in then I would think that you had a problem with your hardware since it's the same on two different systems.

What interface are you using?

[Emdee406]

I am always connected directly into the computer. I'm really starting to think it is the Mbox that has had it. apparently iMac G5's are known to have dodgy power through the buses and that may have killed my MBox.