FRITZ!Box 5490 Service - Knowledge Base

FRITZ!Box 5490 Service

Poor speech quality when making and/or receiving telephone calls

One of the following issues sometimes or always occurs when you conduct calls:

  • You experience disturbances such as echo, dropouts, delays or background noise when making telephone calls.
  • A loud and annoying hiss is heard when conducting calls. 
  • The voice of one or both parties sounds distorted or "choppy".

Important:Some of the settings described here are only displayed if the advanced view is enabled in the user interface. The configuration procedure and notes on functions given in this guide refer to the latest FRITZ!OS

Simply proceed as described below. After each measure, check whether the issue persists.

1 Installing the latest software for your telephone

The following steps are only necessary if you are using a FRITZ!Fon:

2 Excluding repeater(s) as a source of interference

The following steps are only necessary if you use one or more repeaters to increase the DECT range of the FRITZ!Box and the background noise occurs when making calls with cordless telephones:

  1. Unplug all of the repeaters.
  2. Check whether you still hear background noise when you make a call with a cordless telephone while you are close to the FRITZ!Box.
  3. If you no longer hear background noise now, follow the instructions given in our guide Background noise when using a DECT repeater. In this case, the repeater is either not correctly connected with the FRITZ!Box or it was not positioned correctly.
    • If you can still hear background noise, plug the repeater in again and proceed with the following section.

3 Restarting the FRITZ!Box

  1. Click "System" in the FRITZ!Box user interface.
  2. Click "Backup" in the "System" menu.
  3. Click on the "Restart" tab.
  4. Click the "Restart" button.

4 Reducing the in-call volume on the telephone

  • Reduce the in-call volume on the telephone.

    Note:If you would like to reduce the in-call volume on your FRITZ!Fon, press the "down arrow" or "telephone book" icon on the control ring while speaking on the telephone.

5 Registering cordless telephones with the FRITZ!Box

  • Register all cordless telephones with the FRITZ!Box's base station and switch off all other base stations.

6 Restoring FRITZ!Fon to its factory settings and re-registering it

The following steps are only necessary if the issue only occurs with a particular FRITZ!Fon, and you do not experience problems with speech quality when using other telephones:

Restoring the telephone to its factory settings

  1. Press the "Menu" key on the telephone.
  2. Scroll to "Settings" and press "OK".
  3. "Reset" > "OK" > "OK"

Deleting the telephone

  1. Click "DECT" in the FRITZ!Box user interface.
  2. Click "Cordless Telephones" in the "DECT" menu.
  3. Click the button (Delete) to delete the respective telephone.

Restarting the FRITZ!Box

  1. Click "System" in the FRITZ!Box user interface.
  2. Click "Backup" in the "System" menu.
  3. Click on the "Restart" tab.
  4. Click the "Restart" button.

Re-registering the telephone

7 Configuring FRITZ!App Fon for Android

The following steps are only necessary if the issue occurs when using FRITZ!App Fon with an Android device:

Enabling alternative microphone

  1. Start FRITZ!App Fon.
  2. Tap "More" and then "Settings".
  3. Tap the menu key on the telephone and then tap "Advanced".
  4. Enable the option "Alternative microphone".

Adjusting the microphone volume

  1. Start FRITZ!App Fon.
  2. Tap "More" and then "Settings".
  3. Tap the menu key on the telephone and then tap "Advanced".
  4. Adjust the microphone volume step by step.

The FRITZ!Box's echo compensation and traffic shaping functions guarantee high speech quality. However, if you still experience an echo, delays or short dropouts, these are caused by the telephone being used, your Internet service provider or telephony provider, and cannot be influenced by the FRITZ!Box.