Public Class Form1
 
    Const MMSYSERRR_NOERROR = 0
    Const MMSYSERR_BASE = 0
    Const MMSYSERR_BADDEVICEID = (MMSYSERR_BASE + 2)
 
    Private Declare Function auxGetVolume Lib "winmm.dll" ( _
      ByVal uDeviceID As Long, _
      ByVal lpdwVolume As Long) As Long
 
 
    Private Sub getvol() Handles Button1.Click
 
        Dim Retval As Long, AuxReturn As Long
 
        Retval = auxGetVolume(CLng(0), AuxReturn)
 
        If Retval = MMSYSERRR_NOERROR Then
            MsgBox(AuxReturn)
 
        ElseIf Retval = MMSYSERR_BASE Then
            MsgBox("MMSYSERR_BASE")
 
        ElseIf Retval = MMSYSERR_BADDEVICEID Then
            MsgBox("MMSYSERR_BADDEVICEID")
 
        Else
            MsgBox("Error")
        End If
 
    End Sub
 
End Class