How to troubleshoot Voice Quality Issues - With a Premise Phone System and Remote Phones

If you are sending calls out your internet connection using VoIP you are prone to audio quality issues. These audio quality issues can be caused by a number of different factors that often times are very hard to diagnose. The following dependencies exist for good audio quality.

If your phone is remote to your phone system the call passes through the following equipment:

  • Phone
  • Network Switches
  • Remote Site Router
  • Cable Modem
  • Remote Sites Internet Provider
  • Phone System Locations Internet
  • Phone System Locations Cable Modem (or ISP Equipment)
  • Phone System Locations Router
  • Phone System Locations Network Switches
  • Phone System
  • Phone System Locations Network Switches
  • Phone System Locations Cable Modem (or ISP Equipment)
  • Internet
  • VoIP Provider
  • VoIP Providers Network
  • External Carriers Network

With remote phones you must identify if the issue is with the remote phones network or the network where the phone system resides.There are several scenarios that can easily lead you to the answer quickly.

  1. Do phones local to the phone system experience the same issue?
    1. If yes the issue is with the network where the phone system resides.
    2. If no the issue is likely with the remote devices network.
  2. Do other remote phones at different locations experience the same issue? 
    1. If yes the issue is with the network where the phone system resides.
    2. If no the issue is likely with the remote devices network.

Phone, Switch and Phone System Tests

To test if your phone, switch and phone system are processing calls clearly, run this test from a phone local to the phone system. 

  1. Dial *97 or hit your voicemail button.
  2. Dial another extension on the system that is in the same facility.
  3. If both of these tests produce good audio quality you can safely eliminate the Phone, Network Switches, and Phone System as a source of the problem.

Internet Tests

Run a VoIP Quality test: 

In order to run this test, open your local web browser and go to  Once there, click on the geographical dot closest to your physical location:

When you do, the site will check for the 'BCS Connector' required to conduct the test.  If it is not installed, you will be prompted to download and install it.  Once you have successfully installed the connector, refresh the page in your browser.  If the installation was successful, you should see green text in the top right corner of your browser indicating the site detects the connector:

You will now need to click on the dot on the map closest to your physical location again, at which point the test will start running:

Once the test completes you should see output similar to this:

All of this information is valuable in regards to the quality of your connection; pay specific attention to the results from the 'VoIP Jitter', 'VoIP Packet Loss', and 'VoIP MOS' tests.

  1. You are looking for a MOS score above 3.0 (4.5 is the best).  Take a screen shot of the test audit and email it to if you need assistance analyzing the results.
  2. Good Results: No items in Red on the test audit generally means your network and Internet are in good shape. The issue is likely with your VoIP Provider or your Internet providers IP route to your VoIP Provider. 
  3. Bad Results: If you are seeing any items in red you are likely experiencing network or internet issues, continue testing to try isolate the source. 

Ping Test:

Next we need try to identify if your Router, Modem or Internet Connection is the source of the problem. To do this we will use an application called Ping in a command window. Run these tests from both the remote location and the location where the phone system resides. 

Instructions to open a Command window and run Ping

  1. On a windows machine go to start → run → command  or on windows 8/10 just hit the windows icon and start typing command.
  2. This will bring up a window that looks like this:

  3. From within this window let start a ping to your router. Type ping -t where the x's represent the IP for your router. When done control+c will stop the test. Run the test for at least 10 minutes unless you are seeing issues right away. 
    1. We are looking for ping times that are fairly consistent and no dropped packets. If they are jumping around more than 100 MS you are experiencing jitter and the degraded call quality is likely related to the packets being received out of order.
    2. It is best to run this test from a hard wired computer; wirelessly connected devices will experienced unrelated latency due to being wireless. It is even better if you run the test from the switch port on the back of the phone that is having the issue. The below results show a network that has bad audio quality due to packet loss. 

Run through the following scenarios to isolate the problem with your ISP, Router or Cable Modem

  1. Run a ping test directly to your routers IP as instructed above. 
  2. Simultaneously, open another command window and run a ping to google: ping -t
    1. Let the test run for awhile 10+ minutes or until you see clear results.
    2. End the test with control+c
  3. If pings to your router look good yet pings to the internet show issues you must now identify if your router or network load are an issue. 
    1. Good Results: If both tests look good i.e 0% loss and Minimum and Maximum ping times within 100 ms you can skip the next test. You should call your VoIP Provider to open a trouble ticket. 
    2. Bad Results: Run ping tests directly from your internet network port on your cable modem. You will need to disconnect network traffic to your network.
  4. Next plug your computer directly into your cable modem and run the same ping test to the internet. This test is to isolate that your router or network load is not the source of your issues.
    1. Good Results: The issue is likely with your network router switches or QOS settings on your router. Your ISP seems to be performing well with no load on it.  
    2. Bad Results: This is pointing to your ISP as the source of the issue. Call your ISP and report the problem to them. 

Run through the following scenarios to isolate the problem with VoIP Provider

  1. The easiest way to isolate your issue to a specific VoIP Provider is to register a second VoIP Provider to your system. If you are not using Intuitive VoIP as your VoIP Provider we would be an ideal choice as we have no commitment and great rates. Call or email us to learn more.
  2. Run the same tests through a second VoIP Provider to see if the audio issues are still present.

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