Rolling out a new VoIP phone system can improve flexibility, reduce call costs, and future-proof your business communications. But before you flip the switch, it’s crucial to test and troubleshoot the system properly. Skipping this step often leads to dropped calls, jittery audio, or missed messages, issues that frustrate both staff and clients.

In this guide, we’ll walk you through the best practices for VoIP testing and troubleshooting. Whether you’re switching from a legacy phone system or launching a new cloud-based setup, these steps will help ensure a smooth transition for your team.

VoIP Testing: Why It Matters

Before deploying a VoIP system, testing confirms that your infrastructure and internet service can handle the demands of high-quality voice traffic. This process is about more than ticking boxes, it’s how you prevent downtime, optimise performance, and build confidence in the new system.

In the Australian business environment, where remote work, hybrid setups, and interstate teams are common, reliable VoIP is critical. Proper testing means fewer disruptions for your team and a better experience for your customers.

Key Areas to Test Before Launch

Network Performance

VoIP is highly dependent on your internet connection and internal network. Use these metrics to assess whether your setup is VoIP-ready:

  • Bandwidth: Ensure your internet plan has enough upload and download speed for concurrent calls. A good rule of thumb is 100 kbps per call, but it depends on codec.
  • Latency: Aim for less than 150ms for two-way voice.
  • Jitter: Should be under 30ms to avoid voice distortion.
  • Packet Loss: Anything above 1% can degrade voice quality noticeably.

Example: A Sydney-based law firm with 25 staff found call quality issues during testing due to poor Wi-Fi coverage. They resolved this by switching to wired Ethernet connections for all desk phones.

Voice Quality

Test call clarity internally (between staff) and externally (to mobile and landlines). Check for echo, delay, dropouts, or robotic-sounding audio.

Many VoIP providers, including ours, offer test numbers that simulate various call scenarios, this is a useful tool before going live.

Device Compatibility

Test across all endpoints your team will use. IP desk phones, softphones on laptops, mobile apps, and headsets. Make sure:

  • Firmware is up to date
  • Devices register properly with the VoIP server
  • Audio devices (e.g., microphones, speakers) work well in real-life conditions

Common VoIP Issues and How to Troubleshoot Them

Jitter, Latency, and Packet Loss

These are the three main culprits behind poor audio. Causes include:

  • Network congestion
  • Inadequate QoS (Quality of Service) settings
  • Shared networks with bandwidth-heavy applications (like video streaming or backups)

Fixes:

  • Enable QoS on your router to prioritise voice traffic
  • Separate VoIP devices from general office traffic using VLANs
  • Upgrade to a business-grade NBN connection if needed

One-Way Audio or No Audio

This issue often stems from firewall or NAT (Network Address Translation) settings.

Fixes:

  • Check your router/firewall to ensure SIP and RTP ports are open
  • Use STUN or TURN servers for NAT traversal
  • Confirm the SIP ALG setting on your modem is disabled (common issue with Australian ISPs)

Registration Failures and Dropped Calls

If phones can’t register or drop mid-call, it might be a DNS issue, expired credentials, or poor SIP trunk configuration.

Fixes:

  • Reboot devices and check SIP credentials
  • Use a reliable DNS provider (Cloudflare or Google)
  • Ensure SIP timers are correctly configured on the PBX

Testing Tools and Methods

Here are some reliable tools that can help during your testing phase:

  • PingPlotter. Visualise latency and packet loss over time
  • VoIP Spear. Monitors VoIP readiness across various locations
  • Wireshark. For deep packet inspection and diagnosing call flow problems
  • MOS Scoring Tools. Simulate calls and calculate Mean Opinion Score to gauge voice quality

If you're working with an Australian VoIP provider, ask if they provide pre-launch assessment tools or managed testing services.

Launch-Day Checklist

Before going live, run through this quick checklist:

  • ✅ Internal and external calls are clear and consistent
  • ✅ Voicemail, call forwarding, and IVR work as expected
  • ✅ All staff devices are tested and functional
  • ✅ Emergency call routing is in place
  • ✅ Redundancy or backup plan is ready in case of issues
  • ✅ Team is trained and comfortable using the system

Taking the time to complete these checks means fewer issues on day one, and a much better user experience.

Conclusion & Next Steps

A smooth VoIP launch starts with solid preparation. By thoroughly testing your network, devices, and call quality, and knowing how to troubleshoot common problems, you can roll out your system with confidence.

Need help setting up or testing your VoIP system? Contact our team for expert support and tailored solutions designed for Australian businesses.