我对硬件驱动不是很熟

setvolume [device] [left-volume] [right-volume]
Set the volume level of your sound device. The [device] parameter represents the device identifier. In most cases, you should use '0' value for this parameter. Under Windows Vista, you should specify 0 for default playback device or 1 for default recording device.
The [left-volume] and [right-volume] parameters should contain a value between 0 (silence) and 65535 (full volume) that represents the volume level for left and right channels.
Examples:
setvolume 0 0 0
setvolume 0 32768 32768
setvolume 0 0xffff 0

setsysvolume [volume] {Component} {Device Index}
Set the sound volume for your system. Changing this value also affects the sound volume settings under 'Control Panel'. The [volume] parameter should contain a value between 0 (silence) and 65535 (full volume).
{Component} is an optional parameter that specifies one of the following sound components: master, waveout, synth, cd, microphone, phone, aux, line, headphones, wavein. The default value is 'master' (for master volume). Under Windows Vista, the component name must be identical to the one of the device names appear in the sound window of Vista (Control Panel -> Sound). If the device name contains spaces, it must be in quotes.
{Device Index} is an optional parameter that specifies the sound device index. This parameter is useful if you have more than one sound card. If you don't specify this parameter, the default sound card in Control Panel is used.
Examples:
setsysvolume 0x8000
setsysvolume 0
setsysvolume 25000 waveout
setsysvolume 25000 master 1
Vista Examples:
setsysvolume 0x8000
setsysvolume 0 "front mic"
setsysvolume 25000 speakers
setsysvolume 25000 "line in"

setsysvolume2 [left volume] [right volume] {Component} {Device Index}
Similar to setsysvolume, but instead of setting the whole sound volume, setsysvolume2 set the right channel and left channel separately.
Examples:
setsysvolume2 10000 20000
setsysvolume2 30000 0
setsysvolume2 25000 15000 waveout
setsysvolume2 30000 0 master 1