[MPlayer-users] make mplayer play audio from the Line In or the Mic port

[rawgarlic at gmail.com]

According to lspci here is the PCI sound card in this Dell system:


04:01.0 Multimedia audio controller: Aureal Semiconductor Vortex 1 (rev 02)
	Subsystem: Aztech System Ltd AU8820 Vortex Digital Audio Processor
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
Stepping- SERR+ FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort-
<TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 64 (500ns min, 3000ns max), Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 17
	Region 0: Memory at dfbe0000 (32-bit, non-prefetchable) [size=128K]
	Region 1: I/O ports at dcf0 [size=8]
	Region 2: I/O ports at dcf8 [size=8]
	Capabilities: [dc] Power Management version 1
		Flags: PMEClk- DSI+ D1- D2+ AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
		Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
	Kernel driver in use: snd_au8820
	Kernel modules: snd-au8820

This sound card has Speaker, Microphone and Line In ports.
The is a set of speakers connected to the Speaker port and they work perfectly.

How do you make mplayer play the audio from the Line In or the Microphone port?