Iam facing a similar problem with the USB Audio Device of Logitech Web Cam.The code works properly on Mike connected to Sound Card but when i open the mixer such as


result = mixerOpen(&hMixer, 1, 0, 0, 0);

//i see no error.but when i use


    if (result != MMSYSERR_NOERROR) {
        bResult = false;
    } else {
        // get the speaker line of the mixer device
        ml.cbStruct = sizeof(MIXERLINE);
        ml.dwComponentType = deviceType;
        result = mixerGetLineInfo((HMIXEROBJ) hMixer, &ml, MIXER_GETLINEINFOF_COMPONENTTYPE);

mixerGetLineInfo fails to get the Line Information

it would be great if any one can give me solution for this issue...............

Thanks
Prab