Audio output from laptop's speaker and from external headphone

Question

I have observed that even if I have connected my HP external headphone to the audio output jack, still when I play some music then for a couple of seconds the sound output would come from the Asus Eee PC laptop's speaker instead of headphone. This is quite annoying especially if the volume is high. After this short time the sound would come from my headphone only and the laptop's speaker would be quite. Why initially the sound comes from speaker? What is the reason?

Answer 1

According to this answer:

While audio jacks often have switches that can be used for plug detection, most codecs now implement jack sensing that measures the impedance and other characteristics of the plugged in device and make that information available to the processor they are connected to.

Perhaps the detection mechanism is slow in your case, due to a hardware issue, software issue (badly written driver, perhaps?), or a combination of both. Do you have the latest audio drivers installed?