Some laptops treat the speakers and the headphone jacks as two different sound devices, rather than have them as one device and redirect sound out to the headphone when they get plugged in (some computers/mobos do this with the front and back audio plugs).

In these cases the driver will also handle switching the default audio device over as needed on plug events.

Dreamseeker has the issue that it will ignore these changes, in fact if the audio device goes away dream seeker tends to just stop outputting sound, so if you were to unplug then re-plug in your headphones on one of these computers, you may end up having to restart dreamseeker, as well as when you switch from speakers to headphones or manually changes devices for whatever reason.

There is a way to bind to these events or otherwise check this, i know because other applications seem to work fine in this respect.