I am running vista on my desktop machine and when i plug in my speakers into any one of the sound sockets i have only the sound coming out of one speaker, but when i put in my headphones i have sound in both headphones, i have the souns on the machine it is set to centre balance, please help

What sound card do you have in there? More over did you test the speakers to make sure one is not just dead? Simply plugging them into a CD or MP3 player is a good way to test this.

Just reverse the plugs. Left plug to right port, right plug to left port.

If the left speaker is bad, the sound will stay on the right.
If the left output is bad, the sound will move to the left speaker.
And, visa verse.

My Speakers are the type of speakers that you plug into a headphone socket.

Then, can you do as Laughing Man suggests?

IMO it would be a dead speaker, since if headphones work then it is probably not the output, unless the speaker's plug doesnt fit right

urm, yeah turns out speaker is dead, but other works!