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How to Fix VoIP Issues: A Troubleshooting Guide

Wizix TechVoIP

Clear, reliable phone connections are crucial in business. But even though VoIP technology has revolutionized office communications, it doesn’t always work perfectly. Frustrations with VoIP issues can cost your business time and money, place a strain on customer relationships, and create a stressful work environment. In this troubleshooting guide, we’ll go over some of the most common VoIP issues and explain how to fix them so you don’t have to suffer any downtime. 

Seven Common VoIP Issues and How to Fix Them

1: Inconsistent Call Quality

Possible Causes:

Choppy audio, delays, or dropped words can be a frustrating experience during VoIP conversations. These issues may be due to: 

  • Insufficient bandwidth
  • Wi-fi issues
  • Jitter, latency, or packet loss


  • Verify that your internet connection speed meets your VoIP requirements. In most cases, 90-156 kbps is ideal.
  • Prioritize VoIP traffic using the Quality of Service (QoS) settings on your router.
  • Consider switching from Wi-Fi to ethernet for a more stable internet connection.
  • Upgrade your internet plan for improved bandwidth.

2: Echo or Feedback

Possible Causes:

Echoes and feedback are major distractions during VoIP calls. Common causes of these issues include:

  • Acoustic issues in the room
  • Microphone or speaker problems


  • Resolve acoustic issues in the room with sound panels and other solutions.
  • Use headsets or echo-canceling devices to minimize ambient noise.
  • If you already use headsets, check if there is an issue with the microphone or speaker. 
  • Avoid using speakerphone to reduce feedback.

3: Dropped Calls

Possible Causes:

The following issues may cause calls to unexpectedly disconnect:

  • Unstable internet connection
  • Firewall or router configuration issues
  • Timeout settings


  • Improve your internet stability by moving or upgrading your router, or switching to ethernet.
  • Verify that your firewall settings allow both incoming and outgoing audio traffic.
  • Update your router firmware as well as your VoIP software and hardware.
  • Change your router settings to increase the timeout for at least 60 seconds.

4: Jitter and Latency

Possible Causes:

Jitter happens when data packets (pieces of audio) are delivered out of order, making the conversation sound jumbled and incoherent. Latency refers to delays during the VoIP call. These problems can be a result of:

  • Network congestion during peak usage times
  • Insufficient bandwidth


  • Clear the bandwidth space on your local network by investing in a new router or limiting the number of concurrent users.
  • Consider upgrading your internet service for more bandwidth.
  • Install a jitter buffer to reorder data packets. 
  • Schedule important calls during non-peak hours.

5: Unable to Make or Receive Calls

Possible Causes:

The inability to make or receive calls can be costly for your business. If you are unable to establish a connection, it could be from:

  • Firewall issues blocking communication
  • Problems with Session Initiation Protocol Application Layer Gateway (SIP ALG)
  • Outdated software


  • Configure your firewall settings to permit communication.
  • Update your VoIP software and restart the device.
  • Turn off SIP ALG on your router.

6: No Sound/One-Way Audio

Possible Causes:

Sometimes, you may be able to make and receive calls, but one of the parties does not hear any sound once the call connects. This can result from: 


  • Turn off SIP ALG on the router.
  • Check your VoIP settings to ensure that your device is using a common codec that is likely to be compatible with your callers’ devices.

7: Phone Doesn’t Ring

Possible Causes:

In some cases, your VoIP system may be able to establish a connection, but the phone doesn’t ring and you miss important calls. This issue is commonly caused by: 

  • Equipment problems
  • Do Not Disturb settings
  • Call forwarding settings


  • Check that your VoIP handset or desk phone is still registered with your provider.
  • Upgrade your hardware.
  • Turn off the Do Not Disturb setting on the phone if it is enabled.
  • Check your call forwarding settings to see if they’ve been set to forward to another device or employee.

Reliable VoIP Phone Systems for Reno Businesses

By understanding these common VoIP issues and how to fix them, you can enjoy clearer communications. However, if you frequently experience VoIP issues, it may be time to switch to a different provider.  

At WiZiX Technology Group, we offer reliable VoIP phone systems and customizable plans for business owners throughout the Reno area. Give us a call at 866-846-1411 today to learn more about our custom VoIP plans. 


Images used under creative commons license – commercial use (1/16/2024). Photo by Icons8 Team on Unsplash