Question Line In stereo through laptop mic socket

[r0bert02]

ASUS N56VM, Windows 8.1.
The problem: Realtek HD audio (6.0.1.8186) shows 2 channel 16 bit DVD input for the microphone. But it only records the left channel and copies it to the right so in effect giving a mono input.
The mic is 2 channel stereo.
No problem recording stereo internally.
No problem with recording software. (adobe soundbooth cs5, audacity)

Is the problem with the hardware? bus/sound chip/jack plug socket
Is the problem with Realtek?
a missing driver?

Is there any way to check the various stages of the as the sound signal travels from the mic to the ....... where ever it goes!
ASUS "support"???? suggested I contact Adobe!

Or should I just give up and get a USB stereo input adapter.
Any good recommendations should I choose the adapter?
Thanks

 

[CountMike]

Is it standalone microphone or within headphones with single jack ?

 

[r0bert02]

Hi
The aim is to connect a head phone socket of component amp to the microphone jack on my ASUS. I've experimented with a stand alone stereo mic connected to mic jack to try to find out what is going wrong.