I'm having a PCI TV Tuner Card to which an audio cable is given.

i installed the card to my mother board and its working well. The problem is I'm not knowing where to inser this audio cable.It's a four pin cable.But the audio header provision on my Mother board is having 5 pins.So. where to put his cable.I tried connecting to the first four and left the last one,the sound came, but is flickering betweek head phones and line in.So. i cannot hear the sound continously.Do you want to keep a jumper to the other pin??

My Mother Board is : INTEL D945GNT