There is a good chance you’ve experienced poor call quality if you are currently using VoIP or modern phone systems. In this article, we will be discussing the common causes of VoIP call quality issues and what can be done to correct them.

It is simple to diagnose the causes of poor VoIP calls and to find a solution to the problem. Once fixed, these issues should not be ongoing, otherwise you may need to switch to a different VoIP service provider.

  1. Latency

Latency (also known as VoIP delay) is characterized as the amount of time it takes for speech to exit the speaker’s mouth and reach the other person’s ear; when the level of latency is too high on a VoIP call it will produce an echo. There are three types of delay commonly found in today’s VoIP networks.

  1. Propagation delay – In propagation delay, light travels through a vacuum at a speed of 300,000 kilometres (186,000 miles) per second. Electrons travel through fibre or copper at approximately 201,168 kilometres (125,000 miles) per second. A fibre network stretching halfway around the world (20,900 kilometres) produces a one-way delay of about 70 milliseconds. Although this delay is almost undetectable to the human ear, propagation delays in conjunction with handling delays can cause evident speech degradation.
  • Packetising & Handling delay – Packetising is where the speech is digitized and divided into
  • IP packets for transport to the remote destination. Handling delay is caused by devices that forward the frame through the network. Handling delays can affect traditional phone networks. However, in packetized environments, these delays are a larger issue.
  • Queueing delay – Due to congestion on an outbound interface, packets are held in a queue, resulting to queuing delay. Queueing delay ensues when more packets are sent out than the interface can handle in an interval.

The solution for this issue is to prioritise VoIP traffic over the network which yields latency and jitter improvements. Widely used techniques for prioritising VoIP traffic are bandwidth reservation, policy-based network management, class of service, type of service, and multi-protocol label switching (MPLS). A quality VoIP router can resolve several of these issues and can result in business quality VoIP phone service.

  • Jitter

Jitter is a common problem of packet switched networks and connectionless networks. The information is divided into packets. Every packet can travel through a different path from the sender to the receiver. When they arrive at their anticipated destination in a different order than what was originally sent, the outcome is a call with scrambled or poor audio.

It can be difficult to identify what the exact culprit is, since we are using internet connection to make phone calls and send voice data. But the most common causes are:

  1. Wireless networks – While a wire-free network enables mobility, freeing us from seeing cables all over the office, there will be times when we can experience degraded network connection. Wireless network works well with mobile devices, but not dependable in making phone calls.
  • Network congestion – The most common and obvious cause of jitter is an overcrowded network. If too many devices are connected to the same network and are being used at the same time, bandwidth will surely run out and will slow your connection to a crawl. This leads to insufficient bandwidth when making a VoIP call and packets being delivered out of order or dropped.
  • Bad hardware – At least a modem and a router make up our internet network, sometimes switches as well. Bad hardware, such as an outdated modem, a misconfigured router, or a damaged Ethernet cable can lead to call quality issues.

Using jitter buffers minimises delay variations by temporarily storing arriving packets. However,

a large jitter buffer will increase the amount of delay. Packets that arrive too late get discarded.

  • Internal network inadequately configured

If your company has decided to route both data and voice over the same network without properly setting up your network for VoIP traffic, you can expect to have issues with the quality of your calls. Proper network configuration is the solution for this problem. This is, in fact, one of the least expensive and easiest problems to correct. A router capable of Business VoIP that is properly set up will generally fix this issue.

  • Inadequate equipment

Old or defective equipment can create impedance. Other things that contribute to poor VoIP call quality are outdated routers, cable modems, and firewalls. Examine each network element between your computer, VoIP device, and the internet to isolate the issue. Update your router software or better, replace current equipment with new ones.

Many small businesses use their internet connection for both data and voice, which is fine as long as the router has the capability to prioritise VoIP traffic. Call quality can be affected by other users on your network if you do not have a router that is configured for packet prioritisation. For example, another user on your network downloads a large file while you are on a call. Without packet prioritisation, the call’s quality could be degraded. A VoIP router prevents this from happening by giving priority to your network’s voice traffic.

  • Poor internet connection

Most ISPs are not design for VoIP. Transporting voice packets is different from simply surfing the web; it requires an additional set of internet protocols possibly not provided by your ISP. You will need to contact your provider and ask if you can upgrade to business class high speed. Fortunately, most cable and DSL high speed internet providers offer business class high speed that is acceptable in making VoIP calls.

Candour Communications has developed a Telephone Lines in a Box product, making your VoIP lines less reliant on the type and quality of your internet connection. You won’t have to worry about quality issues that can be experienced with your current VoIP lines. Telephone Lines in a Box uses its own data connection via our Enhanced Voice Gateway, so voice quality is always assured.

Another good solution involves the use of such efficient and highly integrated systems that use phones like the Avaya J169.
To know more about what Candour Communications can offer you, give us a call at 1300 651 350 or email info@candour.com.au.