Businesses are enjoying lower phone bills and productivity enhancing features thanks to Voice over IP (VoIP) phone service.
While enjoying all of the benefits of VoIP what happens when things go wrong? You could call up your service provider and they will lead you in a dance through all of their support tiers. Instead, why not take ownership and try to fix the problem yourself.
Related Article: 5 Reasons the VoIP Market Will Reach $88 Billion by 2018
After 10 years helping businesses find a VoIP provider at WhichVoIP.com, many questions have ended up in our inbox from people looking for help when problems occur. There are four distinct categories for these problems. In the following sections, I will address each category, while offering some suggestions on how to troubleshoot the underlying problem.
1. No Dial Tone
No dial tone is a major problem and this tends to be something fundamentally wrong with your setup, for example:
IP phone provisioning
Your provider would have auto-provisioned your phones if you purchased directly from them. If not, manual provision of the phones is necessary, using the SIP credentials given to you by the provider. Without credentials, authentication will fail and you will not hear a dial tone. Verify that your phone is in the “registered” state, indicating that authentication was successful.
Router port forwarding
Typically, your router should forward UDP ports 5060-5090 and 16384-16482, though this number may differ depending on your service provider. Forward these ports and your dial tone problems should disappear.
2. Dial Tone but No Audio
If no audio is evident in one or more directions when making calls, but you do have a dial tone, this is likely to be a port forwarding issue in your router. SIP signaling usually occurs on port 5060 and if you have a dial tone, the signaling is successful. However, the ports that carry the actual audio packets may not be getting through. Ports 16384-16482 tend to be the ones utilized for the audio packets, although provider verification may be necessary here.
3. Choppy Audio
It is very frustrating when the audio breaks-up during your phone calls and many factors could contribute to this:
Internet related issues
Run a VoIP Test to test your Internet speed, packet loss, jitter, MOS score and overall suitability for VoIP. Run it when your audio seems to be good so that you have a baseline and then take snapshots when issues arise. Make sure there is enough bandwidth to support your maximum number of concurrent calls. A 24/7/365 VoIP monitor service should be considered as a long-term strategy.
Change your audio codec to G.729, if you are exhibiting bandwidth related issues since this codec provides additional audio compression, which utilizes less bandwidth.
Quality of Service (QoS)
Turn on router QoS so that prioritization occurs for your voice packets over other data packets on your network. This ensures your phone calls always have enough bandwidth.
Jitter can be a major problem for VoIP calls and if you are seeing excessive jitter when you run a VoIP test, increase the depth of your jitter buffer. Do not make it too large though as the additional delays could become highly noticeable.
We have all heard acoustic echo at some time and in most cases, this occurs when the volume is too high on your speaker and your microphone is picking it up. Reduce the volume on your speaker and see if it fixes the problem.
The troubleshooting tips shared above should help pinpoint the underlying issue for your specific VoIP problem. If they do not help, contact your VoIP provider and explain the steps you followed, if nothing else, this will ensure a fast path to a higher support tier.