[MPlayer-users] Can I play audio from microphone input with mplayer?

[James Board]

Is it possible to use mplayer to play audio from the microphone input?
If so, how (I'm on a Linux PC running CentOS)?

Context: I connected the audio output of my DVR to the PC's microphone
input jack and I'm trying to play that audio through the PC's speakers.  Does !
make sense?  I don't need to record the audio, merely play it.

If this isn't possible with mplayer, what would be the correct tool to use to
do this?  Seems like it should be a common thing.