microphone and FreeBSD 6.2

[Charlie & Root]

the microphone does not work at all

dev.pcm.0.%desc: ATI SB450 High Definition Audio Controller
dev.pcm.0.%driver: pcm
dev.pcm.0.%location: slot=20 function=2 handle=\_SB_.PCI0.AZAL
dev.pcm.0.%pnpinfo: vendor=0x1002 device=0x437b subvendor=0x8086 
subdevice=0xd60
1 class=0x040300
dev.pcm.0.%parent: pci0
dev.pcm.0.wake: 0
dev.pcm.0.buffersize: 16384
dev.pcm.0.vchans: 4
dev.pcm.0.vchanrate: 48000
dev.pcm.0.vchanformat: s16le
dev.pcm.0.polling: 0


Mixer vol      is currently set to  76:75
Mixer pcm      is currently set to  69:69
Mixer line     is currently set to  75:75
Mixer mic      is currently set to  84:84
Mixer cd       is currently set to  75:75
Mixer rec      is currently set to  86:86
Recording source: vol


pcm0: <HDA Codec: Realtek ALC883>
pcm0: <HDA Driver Revision: 20070105_0038>pcm0: unregister: channel 
pcm0:virtual:0:dsp0.v0 busy (pid 929)
 
Help me please.