Why do some wireless earbuds have latency, and what can be done about it?

Wireless earbuds have become the primary choice of music enthusiasts, gamers, and commuters. They’re small, portable, and get rid of the issue of tangled wires. But if you have at some point used one to watch a movie, play a game, or make a call, you may notice a flaw: the audio does not always sync up with what is happening. What you experience is called latency.

Latency in wireless earbuds is between not at all and very much an issue. To understand why it happens and what manufacturers do to fix it, you can better choose which earbuds are right for you. Let’s go over it.

What Is Latency in Wireless Earbuds?

Latency is what we notice as the gap of time between when an audio signal is put out and when we hear it through our earbuds. In wired headphones, this delay is almost nonexistent as the signal goes straight through the cable. But with wireless earbuds, the sound has to travel via wireless protocols in the air, go through small chips for processing, and then play through tiny speakers.

In a 100–200 millisecond delay, sound becomes almost a jarring element in video or gameplay. What your brain is used to is sound that is in perfect time with what you see or do, and when it isn’t, it ruins the immersion.

Why Do Wireless Earbuds Have Latency?

Latency is a result of many steps between your device and your ears. Here are the primary causes:

1. Wireless transmission of data.

Most of what we see in wireless earbuds is still Bluetooth for audio transmission. What we have today isn’t what Bluetooth was made for—it was initially for basic data transfer like that of file or mouse connection. What we get is sound compressed into packets which are then sent wirelessly. That compression and transfer introduces delay.

2. Audio Coding and Decoding.

When you use your phone or a laptop for audio output, it doesn’t send out raw uncompressed sound, which in large amounts would use up too much space and battery. Instead, it encodes it into a format like SBC, AAC, aptX, or LDAC. At the other end, your earbuds do the decoding, which they then play back. This in-between process of encoding and decoding adds in extra time, which in turn increases latency.

3. Noise interference.

Wireless earbuds operate on the same radio frequency band as Wi-Fi routers, other Bluetooth devices, and even microwaves, which may at times cause interference, which in turn may delay the signal or cause retransmission, thus increasing latency.

4. Internal Earbud Processing.

Wireless earbuds are in fact computers which have little processors in them. They run on Bluetooth, have built-in noise cancellation, touch controls, and power management. All of which require processing time, which in turn may add a few milliseconds of delay before the audio reaches your ears.

5. Synchrony of Left and Right Earbuds.

In the world of true wireless earbuds, each earpiece is a separate unit which does not tie in with a wire. They have to stay in sync, which puts the left and right audio channels in perfect agreement. This sync, which they maintain, introduces another element in which delays may occur.

When Latency Becomes a Problem

Not all earbud users report the same level of latency issue. For example:

• Music Playback: A 100 to 200 ms delay goes unnoticed when it’s just music you’re listening to because there is no visual element to which to compare it.
• Video Streaming: Delays are noticed when there is a mismatch between lip movement and sound. Even a 100 ms delay can cause speech to appear out of sync.
• Gaming: This is where we see true latency issues. In fast-moving games, a tiny delay between pressing a button and the action in the game may cause the experience to fall apart.
• Voice Calls: Latency may cause people to talk over each other, but we have seen that modern earbuds do better at this.

How Manufacturers Reduce Latency

The great news is that we have seen a large reduction in latency of wireless earbuds in recent years. Manufacturers have put forth various technologies and design solutions to reduce the gap between action and sound. Here’s what they did:

1. Low Delay Bluetooth Codecs.

A large aspect of latency is which codec is used. A codec is a system for encoding and decoding audio.

• SBC (Subband Codec): The default setting of Bluetooth, which also happens to be the slowest, often results in noticeable lag.
• AAC (Advanced Audio Coding): Present on Apple products. Good quality, but at times not the fastest.
• aptX & aptX Low Latency: Qualcomm developed these, which have seen great success in reducing delay, at times to just 40 ms, which is very much a hard thing to notice.
• LDAC: Sony’s codec, used for high-quality audio. As for latency, it depends on the implementation, but it is better than SBC.

Codec selection is a large factor in what delay you will see. In the design of earbuds for gaming, which codec is used is very important.

2. Game Modes.

In today’s tech landscape, many earbuds come with what we can term as “gaming mode.” Once this mode is turned on, it does lower audio quality a bit, which in turn speeds up transmission. This results in latency that is a fraction of a second, and thus the earbuds become much better for competitive play.

3. Better Bluetooth standards.

With each iteration of Bluetooth, we see an improvement in efficiency. For instance, we see that 5.0 and 5.2 have lower latency compared to the older 4.2. They also bring faster data transfer, improved stability, and better synchronization between devices.

4. Dedicated Wireless Network Protocols.

Some premium earbuds and gaming headsets use their own 2.4 GHz wireless, designed specifically for audio. These have lower latency as they are tailored exactly for audio instead of general wireless communication.

5. Optimized Chip Sets.

In earbuds today, we see an increase in processor speed and efficiency. Modern chipsets do an excellent job of quick audio stream decoding and also manage many functions at the same time with minimal lag.

6. Improved Earbud Synchronization.

Manufacturers have changed the way earbuds communicate. Instead of one main earbud playing the audio and then passing it to the other, which can cause delay, in many present designs each earbud gets the signal directly from the source device, which in turn reduces sync delay.

Tips for Reducing Latency Yourself

Although technology has advanced, you may also do what you can to reduce latency with your existing earbuds:

1. Update Firmware: Many earbuds are getting updated with better latency and stability. See if your earbuds have an app which supports these updates.
2. Use Compatible Codecs: If you have a low-latency option available in your phone and earbuds’ settings, turn that on.
3. Stay Close to the Device: Distance and obstacles may cause delays. Keep your earbuds within a few feet of your device for best results.
4. Limit Interference: Avoid places that are very crowded with wireless signals when you can. Also, turn off any nearby Bluetooth devices you are not using.
5. Enable Gaming or Low-Latency Mode: In many cases, smartphones’ apps that come with the earbuds have a toggle for this.

Why Latency Still Exists

You might wonder: If we have come so far with technology, what is the reason for latency to still be an issue at all? In reality, what we see is that there is a balance being struck between speed, audio quality, and power efficiency.

For example:

• A codec will increase speed at the cost of compression quality, which in turn drains the battery faster.
• High-quality audio streams have a larger data size, which in turn causes delay in transmission and decoding.
• To some extent, we have to lower the quality of sound when reducing latency, which is not what all users want.

Manufacturers have to play with all of these elements to design earbuds that cater to a wider audience while not draining the battery in an hour.

The Future of Low-Latency Earbuds

The divide between wired and wireless is closing very fast. We may see that in the future, latency will become almost unnoticeable. Also, what may play out are:

• Bluetooth LE Audio (Low Energy): A new standard that promises lower latency and better performance. It will also support new codecs like LC3.
• Smarter Synchronization: In the future, earbuds will do an even better job at left-right sync, which in turn will smooth out playback.
• Custom Protocols for Gamers: As it is with wireless gaming mice which have achieved nearly zero lag, in the near future we will see the release of earbuds designed with that in mind via specialized wireless technology.
• Integration with Devices: Smart in-built low-latency modes for gaming and streaming will be present in smartphones, consoles, and PCs.

Conclusion

Wireless earphones are very convenient, but we still see latency as the primary issue they have. This delay is brought on by Bluetooth, audio encoding, earbud processing, and the sync between the two sides. While that delay may not be an issue when playing music, in games, for video streaming, and during voice calls it does become a very large issue.

Today’s manufacturers have made great progress in reducing latency. We see in low-latency codecs, gaming modes, enhanced Bluetooth standards, and better synchronization that today’s wireless earbuds outperform what was available from early models. Also, with the next generation of wireless tech, the delay will be almost unnoticeable.

At the end of the day, what we see is that the earbuds you choose should best fit what you use them for. We can pretty much go with anything handy for casual music play. But if you are a gamer or at all sensitive to audio delays, put in time to get low-latency earbuds out of the box or ones you can game-enable, and in that case, you’ll see a large difference in how smooth things run.