I'm using an intel workstation board with builtin audio. It looked like a 5.1 audio because it has 6 plugs on the back.
The software its running is a realtek hd audio manager. It is running on windows xp 64 bit.
The problem I'm having is that when I plugged in a speaker (a 2.0 speaker) on one of the port and then set the port auto-detection to Line-In, the speaker would work but the sound is very bad.
The voice (vocals) volume is very low and is barely audible at low volume setting. The music sounded normal and not proportional to the vocal. There are also some kind of effect like echo or corridor on the vocal only.
I can confirm that the speaker or the source music is NOT the problem. It must be the built-in soundcard.
I've tried shutting down rthdlp.exe to shutdown realtek sound manager, but no success.
Thank you for your help.