The Complete Audio Guide: Solving the Tricky Problems of Live Sound
For live broadcasts and remote backhauls, our signal sources are genuinely complicated: HDMI/SDI, UVC, network stream pulls and external microphones all connect at the same time. With several audio sources mixed together, many people get confused: which audio should be pushed to the stream? How do I monitor it? What do I do when the sound and the picture are out of sync? And when exactly should noise suppression or channel inversion be switched on?
The MiMEMedia C300/C350 supports a wide range of audio inputs: microphone input, voice-intercom audio, HDMI/SDI audio, UVC audio, network stream audio and media audio. Every source can be adjusted independently, which suits conference broadcasts, sports events, event coverage, emergency backhaul and many other scenarios.
Get started quickly: audio settings on the device touchscreen
Global mute. One tap and every source is muted at once — for those moments when the sound has to be cut immediately.
ON: audio always-on mode. When enabled, this audio channel is output to the live stream. If several sources are switched ON at the same time, the device mixes them automatically. For example, with UVC and the external microphone both on, viewers hear the UVC ambient sound and the host's microphone together.
AFV: audio follows video. This is built for the device's dual-input video switching. Only the audio belonging to the video that is currently the program picture is sent to the stream. When you cut the picture, the sound switches with it, so multiple sources are never mixed by accident — extremely useful for multi-camera broadcasts.
External microphone: three key parameters, ON / NS / INV.
ON: the microphone audio stays on. Once enabled, the microphone is mixed into the live output; several sources switched on at the same time are mixed automatically.
NS: (microphone noise suppression). Applies noise reduction to the microphone input, suppressing the ambient noise floor and fan noise on site. Recommended for noisy outdoor broadcasts.
INV: (channel inversion, left/right swap). Many venues feed the device from a mixing console, and it is easy to end up with left and right reversed — on a phone the sound becomes noisy, thin and hard to understand. There is no need to re-patch the console: simply switch INV on and the device swaps left and right internally, fixing the reversed channels immediately.
New feature | UVC audio delay adjustment
UVC is a USB streaming protocol, and its audio/video latency is not deterministic. It is common for the sound to run ahead of the picture, with the mouth no longer matching. The C300/C350 adds an audio delay adjustment specifically for UVC sources:
Turn on monitoring for the corresponding UVC channel;
Fine-tune the delay value according to how far the lip movement is off on site;
Listen in real time on headphones and adjust until the lips and the sound match exactly — solving the UVC lip-sync problem at the hardware level.
Web console and app: audio configuration is supported too
Audio settings are not limited to the device touchscreen. The web console and the app can also adjust audio parameters, which makes remote debugging easy.
Web console: open Settings → Audio. The volume of each SDI, HDMI, UVC and microphone channel, along with noise suppression (NS) and channel inversion (INV), can all be configured independently, and the parameters stay fully in sync with the device.
App: open the audio settings page to adjust the volume of each source and to switch each audio channel on or off remotely. Even when the director is not standing next to the device, the live audio output can still be controlled.