We have solutions to correct VoIP echo, choppy voice, buzzing and delayed speech.   These common descriptions of VoIP problems with a VoIP connection are the direct result of some other factor.  In most cases, these quality issues result from a few identifiable causes.  Follow these correcting steps and the quality of your calls will show a marked improvement.

 

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How to correct VoIP echo:

The number one cause of echo is from voice traveling out from the earpiece or speaker back into the mouthpiece.  Turning down the volume of the phone can greatly reduce this issue.  Another cause of echo is electromagnetic interference.  This can be the result of positioning the IAD too close to other electronic devices, such as, on top of the computer, or near the back of the monitor, or next to a power strip. These three devices have particularly large electrical fields and should be given extra attention.  But, other devices can also create electromagnetic currents, so it is best not to place the IAD and/or any base station of a cordless phone too close to other devices.  Poor quality splitters, phone cables and other devices between the phone and the ATA can introduce echo due to "bounce back",  caused by impedance variations.  Using cordless phones, can also introduce echo, sometimes the result of outside interference.  To correct echo try these steps:

• Hold your hand over the mouthpiece.  If the echo subsides then turn down the volume of the phone.  *You should actually keep the volume turned all the way down regardless, as VoIP connections are extra sensitive and you will experience better quality by doing so.
• Move the IAD away from other electrical devices.
• Remove any splitters or separate caller ID devices between the IAD and the phone.  In many cases this can cause echo that you hear on your end.
• Try using another phone cord, as some cables can be of poor quality.
• If you are using a cordless phone try to replace it with a corded phone (connected directly to the IAD and see if the echo stops.

For a more technical explanation of VoIP Echo and how it relates to PSTN networks see our VoIP Technical Tutorial.

 

Solve VoIP choppy voice:

Choppy voice on a VoIP connection is usually an issue with insufficient or unavailable bandwidth.  A typical two-way conversation takes about 90kbps on both the upload and download on a G711 codec.  (There are other, more compressed codecs that can reduce the required bandwidth, G729 being a popular one.)  In some cases you could have enough bandwidth from your ISP but a computer application is grabbing the available bandwidth, essentially taking it away from the VoIP transmission.  Usually bandwidth issues result in brief dead spots in the conversation, sometimes described as a stutter or a staccato sound.

• Try turning off all your computers to see if the issue still occurs.
• Test your bandwidth, both upload and download.
• Check for file sharing software, these programs usually run in the background and use your bandwidth to upload files.
• Check your computer for malware and Spyware.
• If your router has QoS, then enable it for your VoIP connection.  Linksys BEFSR41 now has QoS.  [How to enable QoS]

You can do an Upload and Download Bandwidth Test.

Your bandwidth should not be continually less than 80% of your ISP's subscribed level of service.  If it is, then you should have your ISP's technical support look at your connection. 

Keeping your computer free of malicious malware can be a trying experience.  First we recommend, getting the latest version of Ad Aware.  This utility can recognize and remove 90% of these ominous files.  Another good addition to this arsenal would be Spybot Search & Destroy.

Typical bandwidth* usage for different codecs.

• G711 -    87.2kbps -This is the best quality codec.
• G729 -    31.2kbps -A compressed good quality codec.
• G723.1 - 21.9kbps -The codec best for satellite, (more compressed).
• G726 -    55.2kbps
• G728 -    31.5kbps

*These figures are the nominal Ethernet bandwidth one-way and are only for the voice traffic on a single call.  To calculate how much bandwidth would be required you will also want to consider internet use by computers and other devices.  (Also, remember a three way call (two parties called), will take twice the nominal bandwidth.)

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Buzzing, static and interference:

VoIP static, interference and buzzing is usually associated with the introduction of a signal or voltage into the VoIP connection that is then converted into an annoying sound.  In many cases the problem exists within the devices that are connected to the ATA.  Cordless phones can be susceptible to interference from other wireless devices transmitting on the same frequency.  If you are experiencing this type of issue the first thing to do would be to disconnect everything from the phone port of the ATA.  Then connect one simple corded phone directly to the ATA.  If the buzz or static sound is gone then look at one of these possibilities:

• Cordless phones can generate static if the signal is weak.  Weak signals between the base station and handset can be caused by too great of a distance between the two or weak batteries in the handset.  Another possibility could be interference generated by another wireless device.
• A device that could be introducing electrical voltage such as a caller  ID device, or another device.
• Using an incorrect power supply that has a different voltage.
• Having distributed the VoIP though out the premise without disconnecting the incoming line at the demarc.
• An alarm system not integrating correctly with the VoIP.
• A dial-up modem device that is trying to dial out through the VoIP line.
• A baby monitor.  These devices can broadcast on a similar channel to your phone. 

Check the power supply and not only make sure that it appears correct (has the manufacturer's name on it), but is the correct voltage and amperage.  Linksys equipment has different power supplies for different routers.  Check to make sure that if you have two pieces of equipment from the same manufacturer that you are using the correct one.  You may need to check the manuals.  For an RT31P2 you should be using a 12VDC and 1000ma power supply.  When using one that came with perhaps a wireless router (sometimes 500ma) you will experience static on your phone.  Prolonged use of an incorrect power supply could damage the ATA and/or router.

When getting new equipment it would be a good idea to tape a piece of paper with the device's name on it.  We suggest that you tape it at the end where you plug it into the device, as it will make it easy to see when reconnecting equipment.

Connecting the VoIP service into the premise's wiring, which has not been physically disconnected at the demarc, could result in the VoIP equipment receiving voltage, which would  very well damage the ATA.  If you have not already disconnected the previous telecom's wiring at the demarc, and want to connect into the wall jacks, then you will need to do so.  more   If you have already disconnected at the demarc, there should be no voltage being introduced into the premises telephone circuit, other than that which the VoIP is creating. 

Some devices that can introduce voltage and actually interfere with your VoIP service are:

• Alarm systems
• Separate caller IDs

Faults with the wiring throughout the premise can also cause noise or buzzing throughout the lines.  Some conditions can create the following:

Buzzing: Interference can be caused by one or more wires that may have come into contact with metal, (other than the connection terminals).

Static:  Wires that could be loose at a connecting point. Check all wires and connections for secure connections.

Dead Air: Can be the result of wires crossed or coming in contact with another pair.  (For example a red wire crossed with a green wire if 2-pair wire is being used.)

If the buzzing still occurs after a corded test phone was connected directly to the IAD, then look at these possibilities:

• Do you have the correct power supply that came with the device?
• Try plugging in the power supply into another 110volt source.

If all these possibilities have been checked and the issue is still occurring, then the noise may be actually coming from the ATA itself.

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Delayed Speech and Long dead spots:

                                                                          Continued