Instrument track playback through Internal Speakers?!

I’ve got this problem with Cubase that whenever I try to create an instrument track it will play the sound of the VST on my internal speakers of my laptop. (I’ve got a mini jack plugged in for the external speakers) The strange thing is, I first thought it was a sound card problem but when I create a Midi track it does play my sound through the external speakers.
How can this be fixed or is there more information needed to give feedback?

Kind regards