SetOutputChannelGain
output->SetOutputChannelGain(0, output->GetOutputChannelGain(0) * f);
output->SetOutputChannelGain(1, output->GetOutputChannelGain(1) * f);
output->SetOutputChannelGain(channel,
output->SetOutputChannelGain(channel,
output->SetOutputChannelGain(0, m * fl);
output->SetOutputChannelGain(1, m * fr);
void SetOutputChannelGain(int channel,
output->SetOutputChannelGain(i, fOutputSetting.FindFloat("OutputChannelGain", i));