//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// * New Method: Lower BGM Volume For Set Time
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
public void LowerBGMVolumeForSetTime(float howLong, float fadeoutTime = 0.0f)
{
int audioHandlerID = m_oSubsceneAudioHandler.AudioHandlerID;
float startVolume = AudioSourceManager.GetSelectedAudioVolume(m_oSubsceneAudioHandler.AudioHandlerID);
float endVolume = 0.005f;
AudioSourceManager.FadeoutAudioThenFadeBackIn(audioHandlerID, startVolume, endVolume, m_oSubsceneAudioHandler.m_fMaxVolume, fadeoutTime, howLong);
}