I am using ASUS board(Realtek 5.1 Audio, ALC 883, Win7)and connected 5.1 from back panel. Now without unplug we are unable to hear sound of microphone from either back or front panel. Is it possible to without detaching 5.1 speaker jack from back panel I can hear sound on microphone from front panel.
You need to use the audio control application software to set the functions of the board. However, Asus has a lot of problems, especially with audio, documentation, and customer support.
Download the motherboard manual from Asus website, it might have the information you are looking for.