Sound comes out of speakers and headphones simultaneously

I recently purchased a pair of SVEN SPS-702 speakers, however I noticed that whenever I plug my headphones into the speakers, sound continues to come out of one speaker plus the headphones and I can't seem to get my speakers to play sound exclusively through the headphones. I read online that the fault wasn't with the speakers but with their configuration and that I should do it through a driver. The problem is, I can't find a driver for them online. On the SVEN website there is a tab that says DRIVERS/MANUALS but there are no drivers there to download. I dont know what to do, I read online that I should do this through driver for my sound card, but it's old and doesn't have software that allows me to make any custom changes to it. I have windows 7 btw.