9 VoIP Troubleshooting Tips to Fix Everything Right Now

Making VoIP (Voice over Internet Protocol) calls is easy, convenient, flexible, and affordable. VoIP troubleshooting, on the other hand, can be frustrating and time consuming if you don’t know where to look.

Some of the most common issues include dropped calls, mic echo, delay, no audio, or one-way audio.

Fortunately, fixing most of these problems is relatively simple with one of the following:

1. Move closer to the router.
2. Close other applications.
3. Use a different Wi-Fi band.
4. Update router firmware.
5. Disable SIP ALG.
6. Check firewall settings.
7. Change VoIP codecs.
8. Prioritize VoIP traffic with QoS.
9. Use a Wi-Fi booster.

Bonus tip: If your router is more than a few years old, you might want to replace it with one of the best VoIP routers. I recommend give these other fixes a try first — VoIP is old technology that certainly doesn’t need the latest and greatest hardware to work well.

1. Move closer to the router (or restart it)

Because of how routers work, this tip is really effective. If it’s easy for you to move with your device, try this first.

When to use it? You’ll find this tip helpful if you’re taking calls from your laptop or cell phone, and you hear glitchy voices. Poor network connection can result in poor VoIP call quality and cause some delay or packet loss. Signal strength could be the culprit.

Remember that a network’s signal strength, measured in dBm, is not the same as speed. Anything between -50 dBm and -70 dBm is considered excellent to good signal strength. The closer you are to the router, the stronger the Wi-Fi signal will be, and the less jitter you’ll have to deal with.

Why does it work? Wi-Fi signals are radio waves, and like all radio waves, they can be weakened by distance and obstacles. The weaker the Wi-Fi signal, the more likely it is that packets will be lost or altered. This can lead to poor call quality and choppy audio. If you try downloading a file with a poor Wi-Fi signal, you’ll notice how it’s considerably more difficult than when close to the router, even if you’re paying for an excellent download speed. Calls work the same way.

How to do it? It’s not just about getting closer. If possible, try to position your device within the line of sight of the router. The key is avoiding placing it behind obstacles, such as walls and furniture.

What if calls are dropping altogether? Will this work then? Moving closer to the router may help in some cases, but it is not a catch-all solution. An unstable internet connection, network congestion, a poor VoIP service provider, or a VoIP device that’s incompatible with the internet connection might be the cause of the inconvenience. So, before losing your temper, do this:

• Check if your internet connection is stable enough.
• If your network is congested, dial up your ISP’s support number and let them know. (You may want to use a landline or non-VoIP service to do this.)
• Make sure that your VoIP service provider is reliable and has a good reputation.

Finally, you can always restart your router or VoIP device to see if that works.

2. Close unused applications

If you’re using a softphone to make VoIP calls, you might have several other apps running simultaneously, like Instagram, Google Maps, or a weather app. Close them! They could be the reason your calls drop.

When to use it? Try this fix when you are experiencing poor VoIP call quality on a Wi-Fi network, and you have also noticed that some other apps are running slowly.

Why does it work? When you have too many apps open at once, they start contending for bandwidth or RAM, which VoIP calls require. Note that VoIP doesn’t require a lot of bandwidth, but the connection has to be stable. Other open apps may interfere with that connection, resulting in problems with your VoIP call.

How to do it? This depends on your operating system. Here are some tips for closing unused apps on computers:

• On Windows, you can close unused applications by pressing Ctrl + Shift + Esc to open the Task Manager. Then, select the application you want to close and click End task.
• On macOS, you can do it by pressing Command + Q or by clicking the red button in the top-left corner of the application window.

3. Use a different Wi-Fi band

When to use it? This fix is helpful when you’re on a device such as your laptop, but you’re still fairly stationary. The two most common Wi-Fi bands are 2.4 GHz and 5 GHz. You can opt for the 5 GHz band if you notice a poor connection on the other one.

Why does it work? The 2.4 GHz Wi-Fi band is usually more congested and has a longer range. The 5 GHz band has better speed. Despite it being able to provide a better performance because it is typically less clogged up, the 5 GHz band has a shorter range than the 2.4 GHz band. This means that you may need to be closer to the router to get a good signal on the 5 GHz band.

How to do it? You will just need to change the Wi-Fi band settings on your VoIP device. The specific steps to take will vary depending on the device you are using.

4. Update router firmware

When to use it? If you’ve already tried simple Wi-Fi solutions and your VoIP call is still experiencing packet loss and delay, the problem may have to do with your router’s outdated software.

Why does it work? Firmware is software specifically designed for hardware, like routers, TV remotes, or handheld video game consoles. Just like your computer or smartphone needs updates to fix bugs and improve performance, routers also receive firmware updates to tweak up their functionality. When it comes to VoIP calls on a Wi-Fi network, updating the router’s firmware could help make sure the calls sound clear and don’t get all glitchy.

How to do it? Here are the steps you should follow:

1. Find your router’s model: You can find this information on the manufacturer’s website or in your router’s documentation. Check the model and the latest firmware version available.
2. Head to your router’s URL and log in: It’s usually http://192.168.1.1/. If you don’t have the credentials to log in, request them from your ISP.
3. Look for the firmware update section: It might be called Firmware Update, System Update, or something similar.
4. Download the latest firmware: Find it on the manufacturer’s website and save it on your device. Check is the correct version for your specific router.
5. Upload the firmware to your router: You’re almost there! In the router’s web settings, find the firmware update section and choose the option to upload the firmware file you downloaded. Follow any instructions that pop up.
6. Wait for the update to finish: Your router will restart during the update process. Be patient and let it complete the update.

Some ISPs don’t want you to meddle with their routers or modems. That’s why some firmware updates could stop running after you reset your router, which could happen accidentally if the power goes out in your neighborhood. So if you can’t update your firmware, call your ISP and ask them for a replacement.

5. Disable the SIP ALG feature

Many routers come with SIP ALG enabled by default. SIP ALG stands for Session Initiation Protocol Application Layer Gateway, and it’s supposed to improve VoIP performance. Unfortunately, the SIP ALG feature causes more problems than it solves for many users.

When to use it? This wouldn’t be my first fix, but if you have tried other VoIP troubleshooting tactics without luck, I would check to see if SIP ALG is enabled on your router. That could very well be your issue.

Why does it work? SIP ALG is supposed to limit potential issues with VoIP and firewalls on your network. Unfortunately, not all VoIP services and devices communicate in the exact manner SIP ALG expects, and it winds up causing VoIP issues like one-way audio and dropped calls. Turning off SIP ALG can improve things by letting the VoIP calls work without the router getting in the way.

How to do it? Again, the steps to disable SIP ALG will vary depending on your router. However, most routers have a web interface that you can use to access the SIP ALG settings. Once you have found the setting, set it to Disabled or Off. If you can’t find this setting, you may want to contact your ISP.

6. Check firewall settings

Setting up firewalls to follow best practices may unintentionally block VoIP traffic. This can happen for a number of reasons, such as port blocking, protocol inspection, or firewall policies. You could be left wondering why your softphone doesn’t have an internet connection, only to realize that it hasn’t been whitelisted in your OS’s firewall. But then again, a company could have another type of firewall protecting its network, so you should check on two instances.

When to use it? Give this a shot if your VoIP doesn’t work whatsoever and you’ve got a firewall set up. At a business, you should consult your IT department before messing with firewall settings. You don’t want to be the one who brings down the network or leaves a door open to hackers.

Why does it work? Here are some common reasons why firewalls might block VoIP traffic:

• Port blocking: Firewalls can sometimes block VoIP traffic because they don’t recognize the specific “ports” used for VoIP communication.
• Protocol inspection: Some firewalls inspect the content of data packets. If they can’t identify the VoIP protocol, they might block it, thinking it’s potentially unsafe.
• NAT issues: VoIP and firewalls often have trouble with Network Address Translation (NAT). If the firewall doesn’t handle it properly, VoIP traffic can be disrupted.
• Stateful inspection: Firewalls keep track of connections. If they lose track of a VoIP call, they might block it accidentally.
• Security policies: Sometimes, firewalls are set too strictly, unintentionally blocking legitimate VoIP traffic as part of a broader security strategy.

How to do it? If you want your VoIP calls to work smoothly through a firewall, you might have to set limits to its overprotective fence. This involves ensuring the firewall knows and approves the special “doors” (ports) and “languages” (protocols) that your VoIP service uses. Many modern firewalls have options that make this setup easier, like specific settings for VoIP or “VoIP pass-through” features.

7. Use a different VoIP codec

VoIP codecs compress and decompress audio data and allow calls to be sent through the internet. If they aren’t correctly configured or are incompatible with your network conditions, they can lead to typical VoIP call issues that could be solved just by picking a different one.

When to use it? I would try this fix if you know you have a slow internet connection or you have tried most of the other solutions and nothing has worked.

Codecs compress the data packages and should match your internet connection. If your VoIP calls aren’t clear, it could be because the way your voice is sent over using a codec doesn’t match your internet speed. For example, you could be using a “fast” codec on a slow internet connection. So, if you’ve ever experienced choppy, glitchy sounds over WhatsApp or a conference call, it could be because the codecs don’t match the connection.

Why does it work? Some VoIP codecs prioritize voice quality whereas others are better at  conserving data. The former VoIP codecs are suitable for fast internet connections, whereas the latter will work better with slower ones. The default codec may not be the best one for your internet connection. By adjusting your VoIP codec, you can choose the one that’s best for your network speed and the quality you want.

How to do it? Many VoIP apps and devices have a settings menu where you can pick the codec you prefer. The G.729, Opus, and G.711 are considered adequate options by industry experts. If those don’t work, here’s a full post about how to find the right VoIP codec for your needs.

To tweak your VoIP codecs, you’ll want to find out which codecs your VoIP service supports. Once you know which codecs you can use, you can try them out to see which one makes your calls sound the best, based on your network setup.

8. Prioritize VoIP traffic in QoS settings

The QoS (Quality of Service) feature is included with most modern routers, especially those designed for business. Managing QoS for an enterprise is challenging, but for individual and small business use-cases, enabling QoS can solve a host of VoIP issues.

When to use it? If you’ve already tried adjusting codecs or checking the firewall settings and you are still experiencing phone echoing or packet loss, consider using a router’s QoS feature. This is a feature designed to prioritize certain types of traffic, and it can help to improve VoIP call quality by reducing jitter and latency.

Why does it work? QoS can put VoIP calls first in line for network resources. This means that when you’re talking on VoIP, your voice data gets sent and received faster than other data, like web pages or YouTube videos. If you are at a busy office, QoS will allow VoIP traffic a steady connection and deprioritize bandwidth to things like large file transfers. No one cares if their download takes an extra few seconds, whereas choppy audio during a call is really painful.

How to do it? To set up your router to give special attention to VoIP calls, you’ll need to go into your router’s settings. The way you do this can be a bit different depending on your router, but most of them have a web interface you can use.

Once you’re in the settings tab, look for QoS, Quality of Service, Bandwidth Control, Traffic Management or something similar. First, enable QoS if it is not already. The configure QoS so that VoIP traffic and the ports it uses are identified and assigned a high priority level.

The exact steps you need to follow will be a little different from device to device and using different VoIP phone services. Follow manufacturer and vendor guidance (there should be ample documentation for this as most businesses need to enable QoS). Be sure to save your changes and restart your router. This helps your router know that VoIP calls should get special treatment for smoother conversations.

9. Use a Wi-Fi booster

Wi-Fi boosters, also known as repeaters or extenders, are a very popular way for businesses and individuals to solve issues with weak signals or “dead spots” in the office where people get horrible service. Check out this video to see a rundown of the most popular Wi-Fi extenders.

When to use it? If you’re experiencing poor call quality, a Wi-Fi booster may help, especially if you are far from the router or experiencing “dead spots” in a specific area.

Why does it work? A Wi-Fi booster amplifies the Wi-Fi signal, allowing it to reach further and provide stronger coverage. After this boost, it spreads the signal further, ensuring your Wi-Fi works better in those places where your VoIP calls used to sound choppy.

How to do it? Using a Wi-Fi booster is pretty straightforward. First, plug it into an electrical outlet to power it up. It’s like turning on a helper for your Wi-Fi. Once it’s all powered up, it will start looking for networks all by itself. When it finds your network, just connect to it.

Once it’s linked to your Wi-Fi, it will do its magic and make the signal stronger. It could solve your VoIP headaches.

Simple VoIP troubleshooting fixes most issues

VoIP is a widely used standard and many companies rely on it. That’s why you can be confident that if it’s not working all right, you’ll eventually get around it.

If trouble persists, you might want to consider a different VoIP installation process or even a better VoIP business phone service. If they have not already, businesses experiencing VoIP issues consistently should consider setting up a VLAN for voice traffic that is separated from other network traffic.