The Top 4 Issues with Audio Over Live Streaming
1. Too-Low or Too-High Volume
Too-low or too-high volume is generally caused by either not enough gain or too much gain going to your BoxCaster or encoder. This can be caused by several things, but the most common culprits are gain structure, connection/device, and/or too many points of interception.
The BoxCaster Pro lets you fine-tune the analog input gain directly on the unit. The BoxCaster lets you make rough adjustments in +/-3dBFS increments from its Advanced Settings page. Check out this article to learn more about advanced settings. This can help you adjust audio input levels that are too loud or too quiet — especially when you can’t physically adjust other equipment in your workflow.
We recommend you find an input level setting that works well for you and perform fine-tune adjustments on a per-broadcast basis using your upstream equipment, like an audio mixer or video switcher.
Low volume is annoying. It's hard to hear, not easy to correct, and it can be difficult to diagnose. The easiest remedy is to increase the volume going to your encoder/BoxCaster. However, this might be difficult if you have multiple pieces of equipment, because if you change one, you change them all.
The simplest method is to adjust the volume on the piece of equipment closest to your encoder. If you're running a switcher or coming off a split from a recorder, most of those devices have their own volume control. Adjusting these devices may solve the low volume. If you don't have a switcher and use audio directly from the console or source, adjust the volume in 1–2 dB increments until it’s better matched.
Too Much Volume
The technical term for high volume is overdriven, or clipping. This happens when you exceed the device's native input limit. Clipping sounds distorted, scratchy, and boxy — it can be a real headache for your viewers.
The easiest method here is to bring the audio down. Again, you should first target the source closest to your encoder. Gain structure is also key to too much volume. You should take into account how much volume is added or removed by other devices before the signal reaches your encoder.
Note: Depending on what console and type you’re using (analog or digital mixer), each will have a variety of outputs and dB levels they send.
A general rule of thumb is that analog is -10 dB and digital is +4/6 dB. This can have a great impact on your audio levels. Making sure to gain appropriately can help prevent some headaches.
You can always send the audio to another mixer or submixer and make adjustments as needed. Usually sending audio to a submixer can help dial in the audio level, regardless of if it's too low or too high.
Also, don't forget that many devices viewers are watching and listening through have their own volume limits. What sounds loud on one device can sound low on another.
2. Left- or Right-Side Only Audio
Audio is determined by channels, and there are typically only two channels any person will hear — left and right. The technical terms here are mono (left only) and stereo (left and right). If you're hearing audio in your streams coming through only on the left (or even only on the right), then you're streaming in mono. There are a few reasons why this happens:
The connection to your encoder is only sending audio to the left side.
You're sending audio L/R to your encoder, but your cable isn't working properly.
The device a viewer is listening on is set up for mono audio only.
The best way to solve this is to check your connections. Sometimes, audio being sent in stereo from the source is being converted to mono with your cable. Check to make sure your cable is able to handle stereo signals and that you're connecting it to the correct inputs on your encoder.
It’s also important to use the proper connector. If you're running audio from a console with one cable that’s marked for stereo, you should be aware that you're still running mono audio and your cable is converting the left or copying the left to the right side to make a faux stereo signal.
Note: Viewers’ devices sometimes automatically take a mono signal and make it stereo. Advise them to check their device settings to disable that feature.
3. Audio Quality Differences
Your audio quality seems off. You listen through BoxCast and then through Facebook, and it seems different — worse or better. There’s a reason for that.
Most audio is sent in bitrates. Bitrates are the amount of data being sent. The more bitrates, the better. Oftentimes, what happens is a device is sending bitrates at 320Kbps, but then they’re compressed or modified to 128Kbps. If this happens, the device you're sending the stream from may not be set to send 320Kbps and can only send 128Kbps.
To fix this, try sending the highest amount of audio bitrates you can from your encoder. Naturally, the highest that can be streamed is 320Kbps. If you're finding it hard to determine where good audio quality is and isn't, stick to the standard of 192Kbps.
Note: The BoxCaster is only capable of handling up to 128Kbps. The BoxCaster Pro can handle up to 320Kbps.
4. Ground Loop or Noise Floor Hum
Ground loop occurs when the source of your audio (mixer, camera, or mic) is connected to an electrical outlet or power strip that isn’t grounded. What happens is the natural electrical frequency becomes trapped and loops through the circuit chain. This causes either a 60 Hz or 120 Hz hum.
The best solution to remove the ground loop is to ground the source of your autio. If that’s not easily done, use a ground loop isolator. This will cycle your audio signal through a transformer and remove the loop.
Noise Floor Hum
Noise floor hum occurs when your gain or volume on the source is so high you can audibly hear the lowest frequencies. Noise floor sounds almost like ground loop, but it’s more like a hiss than a hum. To get rid of noise floor hum, try a hum eliminator or bring your gain down a little to keep from amplifying the floor noise in your stream.
Remember, mastering audio in live streaming isn't easy. With so many connection types and variables, it takes time to perfect your sound. Audio is a consistent work in progress — you can’t just set it and forget it. With time though, you can learn the nuances of audio over live streaming and gradually improve your sound.
BoxCaster Hardware Specs
The BoxCaster and BoxCaster Pro have their own limits and specifications. Check out the specs for each encoder to learn more: