错误MIXERR_INVALCONTROLmixerGetLineControlsReturns MMSYSERR_NOERROR if successful or an error otherwise. Possible error values include the following. #define MIXERR_BASE 1024//0x0400#define MIXERR_INVALLINE (MIXERR_BASE + 0) #define MIXERR_INVALCONTROL (MIXERR_BASE + 1) #define MIXERR_INVALVALUE (MIXERR_BASE + 2) #define MIXERR_LASTERROR (MIXERR_BASE + 2)Value Description MIXERR_INVALCONTROL The control reference is invalid. MIXERR_INVALLINE The audio line reference is invalid. MMSYSERR_BADDEVICEID The hmxobj parameter specifies an invalid device identifier. MMSYSERR_INVALFLAG One or more flags are invalid. MMSYSERR_INVALHANDLE The hmxobj parameter specifies an invalid handle. MMSYSERR_INVALPARAM One or more parameters are invalid. MMSYSERR_NODRIVER No mixer device is available for the object specified by hmxobj.
#define MIXERR_INVALCONTROL (MIXERR_BASE + 1)
#define MIXERR_INVALVALUE (MIXERR_BASE + 2)
#define MIXERR_LASTERROR (MIXERR_BASE + 2)Value Description
MIXERR_INVALCONTROL The control reference is invalid.
MIXERR_INVALLINE The audio line reference is invalid.
MMSYSERR_BADDEVICEID The hmxobj parameter specifies an invalid device identifier.
MMSYSERR_INVALFLAG One or more flags are invalid.
MMSYSERR_INVALHANDLE The hmxobj parameter specifies an invalid handle.
MMSYSERR_INVALPARAM One or more parameters are invalid.
MMSYSERR_NODRIVER No mixer device is available for the object specified by hmxobj.
我的声卡就没有peakmeter
你可以从系统声卡选项看出来啊