What Are: Dead Air and One-Way Audio?

Lorraine Kelleher at Spearline explains the impact on customers and the causes of dead air and one-way audio.

Dead air and one-way audio are both frustrating but unfortunately common audio issues that hamper voice calls. Dead air is described as a period of time where you can no longer hear the dial tone, ringing, or the other party. It is simply silent.

In the case of one-way audio, one of the parties involved in the call can hear with clarity, while the other is unable to hear at all. Both of these experiences can be very unsettling, frustrating, and irritating for callers.

The Impact on Customers

Research suggests that almost 77% of the public experience a degree of anxiety about talking on the phone and such issues only increase these negative feelings and lead to an unsatisfactory experience for the caller.

Even a few seconds of silence on the phone can feel much longer for a customer, especially as they cannot understand what has gone wrong or why they are unable to speak to an agent.

For both dead air and one-way audio, the common solution is to end the call and redial. Unfortunately, there is no guarantee that they will not have the same experience a second time. In a call center environment, the caller often has to rejoin a potentially lengthy queue for a second time before they can even attempt to speak to an agent again.

Customers often choose to ring when they need a problem resolved urgently or need to speak to a person about a complex issue. They expect to be able to converse directly with a person at the other end of the phone and resolve the problem.

There is also a much greater expectation for first contact resolution and few customers are willing to spend long periods of time on hold, let alone have to call back the business. A report by Arise details that two-thirds of customers are not willing to remain on hold for greater than two minutes and 13% believe that any wait time involved in a call is unacceptable.

Causes of Dead Air and One-Way Audio

There are many explanations for call connection failures and audio problems including call routing issues, network congestion, and gaps in-network coverage. Migrations are also a common reason, with 46% of those migrating to VoIP falling victim to one-way audio problems.

It is important for organizations that the root cause of the issues is identified. If the dead air occurs on only one side of the call, then the issue could range from a simple hardware malfunction to network configuration problems.

At times, the voice packets which carry the voice data may not be able to successfully travel in one or both directions.

Call control packets run independently of voice packets. These call control packets handle procedures such as call setup, routing, connecting, and codec decisions. This means that even when these packets can each correctly reach their designated endpoint, the call can still face issues that need to be addressed.

Firewalls may lead to the blockage of specific ports and hence the obstruction of voice streams. In such cases, SIP call handling may continue to suggest that the call is stable, even though the voice packets are only able to flow in one direction.

VoIP calls in particular can be severely impacted by issues such as dead air. When Network Address Translation (NAT) is utilized in the communications path and misconfiguration occurs, only one-way communications between devices may be authorized.

Asymmetric routing may also be a potential cause of one-way audio. This occurs when one path takes a short route with low levels of latency and the other direction of the call takes an alternate, longer path which suffers from high latency. As a result, the return path can break the audio path for a part of the call.

The good news is that there are solutions to dead air and one-way audio! Some network monitoring tools do measure a selection of audio quality factors, but this is often very limited in its visibility and Root Cause Analysis (RCA) abilities.

Spearline provides customers with a comprehensive view, and most importantly, an end-to-end perspective across the global carrier networks. Our toolset helps businesses to manage and improve their telecommunications service quality and enhance the customer experience as well as allow greater RCA capabilities.