&channelcount&ac126&inputchannels=N tells the audio capture device explicitly to select N-number of audio channels. &proaudio you want want to disable stereo-audio capture, particularly if you are using an XLR to USB microphone preamp that has two channels, but only one microphone connected.&mono to the view-link or add &inputchannels=1 to the respective guest invite-link.&monomic is the same as &inputchannels=1. This was added in VDO.Ninja v22.