Grandstream FXO FAQ

FAQ - Grandstream GXW 410X Gateway

When I call an outside party and the party puts me on hold with no music or sound, I am disconnected after 60 seconds. Is there a way to change this?

On the FXO-Lines Page there is a setting called Silence Timeout. Set this value to however many seconds you wish to remain connected to a silent line. (A good setting would be 3600s a.k.a. 1 hour).

How do I ensure that the Grandstream is on the latest firmware?

1. Navigate to the Advanced Settings Page
2. Ensure HTTP is selected for the method to upgrade
3. Set Firmware Server Path: to firmware.grandstream.com
4. Set Automatic Upgrade to YES
5. Set Allow DHCP Option 66 to override server to No
6. Click Update at the bottom of the page
7. Click Reboot

The upgrade may take as long as 20min when done through the internet, so allow plenty of time for this. While up- grading the LED will blink. When the LED returns to normal, the device has completed its upgrade.

How do I adjust the Call Volume?

First, please consider that analog lines are supposed to be individually isolated electrically.  This means that you may have to adjust line volumes individually.  Be sure to specify the volume per line if your lines exhibit different electrical characteristics.

In order to adjust the settings:

1. Navigate to the Channel's page
2. Increase Tx to PSTN Audio Gain for issues with external party volume
3. Increase Rx from PSTN Audio Gain for issues with internal party volume

Note that you will have to restart calls in order for changes to be applied.

I am having general call quality issues.  Voice is choppy or unintelligible.

Before performing generic analog line troubleshooting.  You may want to set the following settings to ensure optimal performance: Silence Suppression and Echo Cancellation.

1. Navigate to the channels page
2. Under Channel Voice Setting :

Set Silence Suppression to:

ch1-4:N;

and/or

Set Echo Cancellation to:

ch1-4:N;

Note that Silence suppression can always be turned off safely, but you may have differing results turing off echo cancellation depending on your particular environment.

If you are not successful in resolving the problem with the above settings, please ensure that your firmware is updated to the latest.

Additional Resources regarding analog line issues and VOIP/Digitial Systems:  Sandman

I am having difficulty with line disconnect using Comcast Cable Lines.

If you are using Comcast Cable as your line provider for Analog lines, you should note that Comcast uses Line Voltage drop for disconnect and the timing on this is 900 ms. To make certain the Grandstream is configured optimally you should log in to the Grandstream. Then Navigate to the FXO Lines page. The first item on this page is Enable Current Disconnect and by default this is set to on or Yes. Beneath this entry is the entry If enabled, use threshold: and the default value is 100 ms. You should change this to 900 ms when using Comcast Cable lines. Additionally this information is applicable when using the Ipitomy IP 400 platform for line integration also. Make sure to save and reboot the Grandstream after applying this change. NOTE: On any analog line, you should match this field to the timing value that the provider is sending. As this value is not standard industry wide.

I am getting echo on trunk calls, but not on ext to ext calls

Typically we have found echo on analog trunks to be caused by the trunks themselves. You will likely have to contact the provider to resolve this, but there are a few things you can try to help alleviate the problem while working with the provider.

• Ensure that Echo Cancel is enabled in the Grandstream
• Since echo is typically caused by "hot" lines, you can lower the dB gain to help. This is found in the Grandstream under the Channels page.
• Check with Sandman for other solutions, and how to test the properties of the lines so you can relay the issue to the provider accurately.

Having issues with DTMF being recognized when calling out

• Set the SIP Provider in the PBX to DTMF mode rfc2833
• Set the DTMF mode in the Grandstream (found under the Channels page) to rfc2833