Diagnosing Bad Call Quality

Diagnosing Bad Call Quality

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Our servers are housed in datacenters guaranteed for 24x7 uptime.  Our servers have direct, dedicated, fiber-optic connections to multiple carriers in each datacenter.  Our carriers and PrimeVOX are constantly monitoring the equipment and connections for packet loss. If packet loss is detected, carriers and PrimeVOX will take appropriate actions.

That being said, 99.997% of all call quality problems happen at your (or your customer's) site/ISP.  The following are some troubleshooting steps that you can perform prior to reaching out for technical support.

Diagnostic Process for NO AUDIO:

     1.  Make sure the phone's handset is properly connected to the phone.

  • Check the cable, make sure it's firmly plugged into the handset.
  • Check the other end of the cable, and make sure it is in the HANDSET/TELEPHONE port on the base of the phone.  The handset will NOT work if it's plugged into the Headset port!

     2.  Make sure you are NOT using a detangler (one of those devices that allows you to rotate the receiver 360 degrees without tangling the cord). If you are, remove this.

     3.  It is possible your firewall/router/modem is blocking our phones. Submit a ticket to support@primevox.net and we will happily check.

Diagnostic Process for SCRATCHY/JITTERY AUDIO:

     1.  Check your internet connection, and make sure you're getting the speeds your ISP says you are getting.

     2.  Ask your IT team if your router is under high load or high stress.

     3.  Rebooting your router and/or cable modem can absolutely fix issues.  Be aware though, this will knock your internet offline for a few minutes!

     4.  If all else fails, submit a ticket to support@primevox.net

What causes bad call quality?

  • Jitter (30%)
    • Jitter, which has roughly a 30% negative effect on calls, is the measurement of a connection's consistency, by measuring the amount of time (in milliseconds) between packets. If packets are arriving at incorrect times, the jitter is too high and the audio can become robotic or fractured.
  • Latency (10%)
    • Latency can sometimes be responsible for bad quality, specifically laggy (slow) audio. This can be due to your ISP having too many hops within their network, or your network being too large or having too many NAT layers.
  • Packet Loss (60%)
    • Packet loss has the largest probability when experiencing bad call quality. Loss can come from just about anywhere: your own network, wifi, a switch, your router, your modem, your ISP's backbone, another ISP's backbone, etc.

Diagnostic Process for Cloud Softphone Apps:

     1.  Check the audio settings. In some cases, different Audio Codecs vary in sound quality, the bandwidth required, etc. This can be adjusted for you, as necessary. We recommend using "Force uLaw" instead of g729 as the default Audio Codec for VOIP Applications depending on the quality issue you are experiencing, this may help.

     2.  If all else fails, in some cases, all that is needed is a simple Cloud Softphone Application Reset. Ask PrimeVOX Support to reset your Cloud Softphone Application. Once you receive a new QR Code, simply select Application Settings>Reset Application, and scan the new QR Code. This can improve call quality issues in most cases

Why is this happening to us?

Some routers and firewalls are known to have bad performance (see  Working with ISPs / Internet Providers).  Some ISPs install very cheap modems with very low-performing processors. When a modem's CPU is overloaded, it starts to back up packets, increasing jitter. Then, it starts to simply drop them, resulting in packet loss.

"But Internet is working just fine on my computer, so it MUST be my phone"

Computers have the ability to make up for lost packets. They can re-request packets or buffer information. You can even watch a decent quality video on line and have any of the above issues going on since it pre-loads the audio and video (or buffers). Real time voice traffic cannot make up for these Internet issues, so you will nearly always experience symptoms of Internet issues on your phone before you notice it on your computer. 

 

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