How to improve SIP call quality
There are 4 major factors that affect VoIP call quality: headset, computer performance, network adapter and Internet connection.
1. Headset
We strongly recommend to use USB headsets. It's even better to use call center USB headsets with noise cancelling microphones for the best call quality. Jabra and Plantronics are well known for their high quality call center USB headsets.
Analog headsets with single or pair 3.5 mm Jack connectors as well as laptop built-in speakers or computer speakers may cause an echo: other people hear an echo when they are on an audio call with you or your call center Agent. Softphone.Pro echo cancellation feature can reduce echo, but it can't resolve the issue totally.
2. Computer Performance
Softphone.Pro as any other computer program uses computer resources: CPU, memory and network.
Make sure that your CPU usage isn't critical when you're on call. Open Task Manager and check for programs using excessive CPU, memory and disk I\O. Close those programs or pause resource consuming tasks in those programs.
Open Task Manager and check for programs using excessive your network bandwidth. Torrent clients or video and audio streaming usually cause enourmous network usage.
3. Network Adapter
Using wireless network adapters (Wi-Fi, WiMAX, 2G, 3G, 4G) for SIP and VoIP calls usually produces acceptable results, but an Ethernet wired connection will guarantee the highest quality connection.
4. Internet Connection
Internet connection issues can make calls difficult or even impossible, from echoing and popping noises, to distortion, one-way-audio, and dropped calls. When your call quality suffers, please check the following Internet connection quality metrics:
4.1. Bandwith
Minimum required bandwith - 100 Kbps Up and Down.
4.2. Packet loss
Acceptable packet loss - 5%.
4.3. Latency
Acceptable latency - 100 ms.
4.4. Jitter
Acceptable jitter - 15 ms.
As you can see, many factors affect VoIP calling quality. Anyway we guarantee Softphone.Pro high call quality if you follow the recommendations above.
As much as we'd love to help, computer and network diagnostic is beyond what we're able to do for customers. Please contact your system administrator and SIP provider's technical support for assistance. You can also configure Softphone.Pro to send diagnostic information to the SIP server.
5. How to check diagnostic information in Softphone.Pro
If you have encountered degraded VoIP call quality, for example:
- you can't hear the other party,
- other party can't hear you,
- sound is interrupted,
- you hear an echo,
- sound is delayed,
you can perform initial diagnostic and send the results to your system administrator to troubleshoot. Please follow these instructions:
1. Find the call you're interested in in the Call Log and right-click it. Select Diagnostic information from the menu:
2. You will see the window with the information about the call: phone number, call duration and various network metrics.
You should look at:
- RX: Total number of packets - number of packets received. If the value is 0 that means softphone didn't receive the data from the other side of the call. Check your firewall or antivirus settings. Contact your system administrator or provider for help with your network configuration.
- TX: Total number of packets - number of packets sent. If the value is 0 that means softphone couldn't send data to your PBX. Check your firewall or antivirus settings. Contact your system administrator or provider for help with your network configuration.
- RX: Total number of packets lost and TX: Total number of packets lost - number of received packets lost and sent packets lost. If the values are much greater than 0 packet loss is observed. If you're using wireless network connection try to switch to wired connection. Contact your system administrator or provider to find out the reasons behind packet loss in your network.
- Jitter statistics: Average delay - average delay during packets transfer. Contact your system administrator or provider if the value is higher that 100 for help with your network configuration.
- Standard deviation of delay (also known as jitter). If the value is greater than 15, contact your system administrator or provider for help with your network configuration.
3. Make a screenshot of the diagnostic information window and send it to your system administrator or PBX support for investigation of degraded VoIP call quality.