Computer Speakers Buzz When Laptop Is Turned On.

Hi,
I am having a problem turning on my laptop and computer on at the same time.
When I turn my lasptop on my computer speakers buzz that are connected to my computer.
My laptop and computer are not connected together. The only thing I have plugged into my laptop is the power. When i lift my laptop up and move it around the buzzing changes and can get louder and quieter. Then I plug the LAN into my laptop to connect to the internet and the buzzing on my computer gets even louder. I can't test my laptop without any wires as it does not have a battery. Theres A computer in the living room which is also connected to the LAN but nothing happens to my computer when that one is on. Otherwise my computer and laptop both work perfectly. Does anyone know what is causing this?

You help is greatly appreciated.
Thanks.

The only thing I can figure is maybe some feedback between the two.
Do you have a mic on the PC? If so, how do you have the capture volume set?
If it, high enough, then the laptop speakers could be giving a little feedback to them, which would explain why the 'buzzing' changes while you're moving the lappy around.

I know it is very strange.
There is no mic on the computer just Line In which has a Dreamcast and Wii.

Sounds like electrical crosstalk of some sort. If its a lowish buzzing rather than high pitched screeching, then it could be mains frequency pick up. May be more to do with your laptop's power supply than the laptop itself. Is the laptop's power supply, or the mains lead into it, near your speaker cables at all? If so then try rerouting it.

This sort of crosstalk does not need any direct connections, just close proximity allowing the magnetic field generated by one thing to induce electrical current in another. Power supplies and mains cables are good candidates.