Audio not coming through headphones..

[SFD07]

This is a strange one for me..

I have Vista Ultimate installed onto a Vaio Laptop (VGN-FE650G) and just tried plugging in my headphones for the first time.

When I plug them in it disables the sound coming from the speakers but I don't hear anything in the headphones. I first assumed it might've been a bad set and plugged in my good ones - still nothing from Media Player or iTunes. I went into the playback options and see:

Speakers - High definition audio device - Working (checked as default)

Headphones - High definition audio device - Working

When I unplug the headphones it changes to:

Headphones - High definition audio device - Not plugged in

So it's obviously recognizing them.. just not outputting sound. I've checked all the audio levels and it's not that either. I've also tried changing the headphones to the default audio device without luck.

In the same menu which lists the speakers/headphones is an audio bar which gives a visual look at the audio coming through each device (so if music is playing then the audio bar will start moving around to indicate the sound levels -- for headphones there is no sound coming through.

I went into the headphones options and pressed the "Test Sound" button which played back perfectly on the headphones (and displayed the tone on the audio bars).

Any ideas what might be the problem? I like to use the laptop away from the house and often make much use of the headphones.