How to Improve VoIP Call Quality & Reduce Latency

Voice over IP (VoIP) has become a business staple due to its flexibility, scalability, and cost savings. But all that’s irrelevant if calls aren’t clear. Glitchy audio, long delays, and dropped calls irritate users and can damage a business’ professional reputation. For IT teams and business owners, optimizing VoIP call quality and minimizing latency is a business must.

This article will cover everything you need to know about VoIP call quality problems, how to diagnose them, and the best strategies for tuning your VoIP network to achieve clear, reliable calls.

What Affects VoIP Call Quality?

A number of issues can lower VoIP audio quality, but most call quality issues can be traced back to three root causes: limited bandwidth, misconfigured network equipment, or unmanaged traffic.

The key to fixing these issues is identifying which problem, or combination of problems, is causing issues such as jitter, lag, or echo. Here are a few considerations:

• Bandwidth Availability: Insufficient or variable allocation of internet bandwidth can cause call quality to drop, particularly at times of high network usage.
• Network Congestion: Other network traffic from file downloads, video streaming, and cloud file syncing can swamp your network.
• Jitter in VoIP and latency: Fluctuations in packet delivery time (jitter) and/or high data transmission delay (latency) can cause choppiness or sync problems.
• VoIP Packet Loss: Loss of audio data packets can cause robotic sounds, silences, and gaps in your conversation.
• Hardware or Router Issues: Older or consumer-grade routers may lack the ability to efficiently prioritize VoIP traffic.
• Codec Configuration: Configuring the wrong audio codec can increase bandwidth requirements or decrease voice clarity.

How to Diagnose VoIP Call Issues

The first step to solving any VoIP quality issue is diagnosing the source of the problem. Here are a few ways you can go about this.

• Consistency of Issues: Sometimes a call quality problem is intermittent and can only be reproduced at a certain time of day or with a specific call. Make sure the issue is consistent.
• Run a Speed Test: Look at the bandwidth and latency in your current internet connection with a speed test.
• Inspect Hardware: Check for loose cables, firmware updates, and underpowered routers in your current hardware setup.
• Analyze Data Packets: Use a network monitoring application to track data flow and visualize how your packets are behaving.

Monitoring Tools You Can Use

• PingPlotter – Graphical analysis of latency and packet loss over time.
• Wireshark – Deep packet inspection tool to analyze VoIP streams and pinpoint issues.
• VoIPmonitor – VoIP-specific traffic analysis and troubleshooting tool.
• Mean Opinion Score (MOS) is a widely used diagnostic metric that quantifies the perceived quality of an audio call. It’s rated on a scale from 1 (bad) to 5 (excellent). MOS factors in jitter, packet loss, and latency to provide an overall call quality score.

Key Diagnostics Metrics to Track

• Jitter < 30 ms is ideal
• Latency < 150 ms one-way is ideal
• Packet Loss < 1% is ideal
• MOS Score 4.0 or higher is ideal

Five Network Optimization Tips to Improve VoIP Call Quality

A good network infrastructure is one of the building blocks for good calls. Here are some things you can do to help your network optimize VoIP call quality.

1. Prioritize VoIP Traffic with QoS (Quality of Service)

QoS is the ability to configure your network devices to ensure that voice packets are delivered to their destination without unnecessary delay. The service allows the network to prioritize VoIP application data on the network. That means the configuration works by allowing users to change their router settings so that the router transmits VoIP applications ahead of other packets.

2. Use a Wired Connection Instead of WiFi

Wireless connections are convenient but less reliable for critical applications. WiFi is easily affected by interference and other problems such as a variation in signal strength. A wired network connection is more reliable and is less likely to suffer from jitter problems in VoIP applications.

3. Check Your Bandwidth Usage

Every active VoIP call consumes up to 100 Kbps of bandwidth in both directions. That means a single call consumes 200 Kbps. If you have more calls at the same time or your network is doing other heavy jobs, the network may not have enough bandwidth for VoIP calls. Monitor your bandwidth usage to see if your network upload and download speeds are sufficient.

4. Isolate VoIP from Heavy Network Traffic

Where possible, isolate VoIP traffic from other networks, preferably on its own VLAN. At the very least, avoid conducting other heavy network traffic activities, like cloud backups or media streaming during work hours, unless those applications are well prioritized.

5. Connect to a Fiber Connection

Some may wonder does fiber connection improve the quality of VoIP calls? The answer is fiber internet provides symmetrical upload and download speeds. Fiber also has low latency, jitter, and high stability. All this makes fiber a great choice for VoIP applications since it minimizes jitter and packet loss, and will support more calls simultaneously than cable or DSL.

A fiber connection from 24-7 & West Wisconsin Telcom is an excellent choice if you want to get great voice quality for your business. Upgrading to a business-grade fiber plan is one of the most effective ways to improve the internet for VoIP and eliminate bottlenecks.

Read More: How to Transition to Fiber Internet for Small Business

Choose the Right VoIP Hardware and Software

Physical hardware and software affect VoIP performance. High bandwidth doesn’t matter if the hardware’s sub-par. The best router for VoIP will offer advanced QoS, traffic shaping, and VLAN support to help manage and prioritize voice packets. Consider the following hardware and software:

• Router: Get the best routers for VoIP, like those that support advanced QoS and VLAN functionality.
• Headsets/Phones: Noise canceling headsets and VoIP-optimized desk phones can enhance audio quality.
• Switches: Large networks can benefit from VoIP-optimized switches to aid in traffic segmentation and stability.
• Softphones vs. Desk Phones: Softphones allow for flexibility but may be negatively affected by running on underpowered PCs. Desk phones usually have more consistent quality.

Note that incorrect or outdated network settings can introduce bottlenecks that degrade VoIP performance, even on fast connections. Simple upgrades like replacing outdated routers and ensuring consistent power delivery can significantly improve VoIP connection reliability.

Use the Best Codec for Your VoIP Needs

VoIP audio codecs compress voice data so it can be efficiently sent over the Internet. The drawback is that every codec has a tradeoff between quality and bandwidth:

• G.711: Uncompressed, high-quality audio. Uses approximately 87 Kbps per call. If bandwidth is not an issue, use this codec.
• G.729: Compressed, lower-quality audio. Uses approximately 32 Kbps per call. Useful when bandwidth is limited.

Select the codec that best fits your internet bandwidth and call quality requirements.

Cloud vs. On-Prem Voice Platforms and Latency

The location of your VoIP systems and supporting infrastructure can also affect performance.

Cloud-based VoIP is inherently more flexible and scalable, but can introduce higher latency, especially if your upstream ISP connection is congested or of poor quality.

On-prem VoIP platforms provide more control over your call routing and latency, but require significant upfront investment and ongoing management.

Hybrid solutions and edge computing offer a middle path, shifting critical real-time voice processing closer to the endpoints while leveraging cloud flexibility for less latency-sensitive components.

If your latency is unacceptable, shifting to a local or hybrid model may be a solution. To reduce VoIP latency, consider using a wired connection, segmenting your traffic with VLANs, and avoiding overloaded cloud routes during peak times.

Advanced Options for Businesses: SD-WAN and VPN Optimization

Businesses with multiple locations or large operations can use more advanced networking tools to optimize VoIP performance:

• SD-WAN smartly routes VoIP traffic over the fastest and most reliable network paths at any given moment, minimizing the chance of VoIP call drops and maximizing overall stability.
• VPNs should be configured specifically for VoIP to prevent added latency. Consumer-grade VPNs should be avoided for business VoIP optimization.
• Failover configuration using SD-WAN or dual WAN routers can automatically switch to backup or secondary internet lines if primary ones go down, which can help minimize call drops in VoIP systems.
• To reduce call drop in VoIP systems, implement dual-WAN routers and SD-WAN with automatic failover to maintain connection during outages.

For organizations with multiple departments or high call volumes, optimizing business VoIP performance requires a holistic view of both infrastructure and software. By combining robust hardware with a fiber connection and intelligent routing, businesses can achieve consistently high-quality calls across all locations.

Regular Maintenance and Monitoring

Keeping your system optimized isn’t a one-time task. Build a routine around VoIP maintenance:

• Run speed and latency tests monthly to spot degrading performance early.
• Update firmware on routers, phones, and network switches regularly.
• Revisit QoS settings periodically, especially after adding new users or services to your network.
• Conduct VoIP call quality testing quarterly using your chosen monitoring tools. Proactive monitoring can prevent small issues from becoming large disruptions.
• Monitoring SIP call quality alongside other VoIP metrics can help identify specific signaling issues affecting audio clarity.

Tip: Double-check your VoIP QoS settings periodically, especially after network upgrades or adding new connected devices.

When to Call in the Pros

There are, of course, times when even the best-laid VoIP plan may fall short. If you’ve found yourself battling chronic packet loss or jitter that internal staff can’t fix, if your business is multi-office based and you need similar quality and features at every location, or if you have a high call volume where even small problems can affect customer service and employee productivity, you may benefit from bringing in a professional.

A consultant who specializes in VoIP or a managed service provider like 24-7 & West Wisconsin Telcom can provide strategy support, equipment guidance, and full VoIP network optimization.

VoIP Quality Is Achievable with the Right Setup

Reducing latency and enhancing VoIP call quality is an effort that requires action across multiple layers, but it’s certainly not an impossible task when the right strategies, equipment, and network configuration are in place. Whether it’s adjusting your QoS settings and VoIP quality metrics or upgrading your fiber and VoIP hardware setup, small tweaks can make a big difference to the quality of your voice calls and help your VoIP calls rival landlines for reliability and quality.

Want to take steps to upgrade and optimize your VoIP setup? Begin by conducting a network audit and learning more about advanced solutions with 24-7 & West Wisconsin Telcom’s Hosted VoIP services, business internet plans, and custom networking support. Let’s make sure your business voice communications are always crystal-clear, rock-stable, and totally professional.