LOGITECH 2313 sPEAKER sYSTEM

They are Z313 Speakers not "2".

Convenient control pod with headphone jack for easy volume and listening control
Sometimes you like your music to play softly in the background. Other times, you're in the mood to crank it up. Either way, the control pod puts total volume control at your fingertips. You can also turn the power on and off at the touch of a button. And when you want to listen in privacy, just plug your headphones into the built-in jack and you're good to go.

This would suggest the sound is controlled with a combination of the Unit Volume control and Windows Volume Control.

Basics;
Play a youtube video or mp3....whilst doing this
Turn Windows volume up, can you hear a sound play from the speakers?

If yes;

plug in the headphones, can you still hear the music playing?

If not:

Do the headphones have a separate volume control? if yes turn it up

if you still cant hear the music:

turn the volume up on the speaker volume control

if you still cant hear the music:

Do the headphones work in any other source? stereo, phone, tv?

What make are the headphones?


IF you can hear sound through the headphones before attempting any of the above, what are you trying to change the volume with?
The Volume control on the speakers or the volume control in Windows?

Sorrry for the inquisition, but you didnt give an elaborate description of the problem. Theres always moar detail!