FRITZ!Box 7330 Service - Knowledge Base

FRITZ!Box 7330 Service

Telephone connected to FRITZ!Box rings although no one has called

Occasionally a telephone connected to your FRITZ!Box rings although no one has called you, or it rings immediately after ending a telephone call and hanging up, or the telephone continues to ring although the caller has already hung up. When you lift the receiver, you hear a dial tone.

Note:All instructions on configuration and settings given in this guide refer to the latest FRITZ!OS for the FRITZ!Box.

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

1 Disabling the option "Message waiting indication on the telephone (MWI)"

The following steps are only necessary if the telephone is connected to the analog extension "FON":

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "Telephony Devices" in the "Telephony" menu.
  3. Click the (Edit) button for the respective telephone.
  4. Click on the "Telephony Device Features" tab.
  5. Disable the option "Message waiting indication on the telephone (MWI)".
  6. Click "OK" to save the settings.

If the telephone now no longer rings, then you have new messages in the mailbox of your landline telephony provider or internet telephony provider. The FRITZ!Box calls to notify you that you have new messages since your telephony provider supports MWI (Message Waiting Indication).

2 Disabling the alarm

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "Alarm" in the "Telephony" menu.
  3. Disable the alarm.
  4. Click "Apply" to save the settings.

3 Checking the cabling

If you are using the FRITZ!Box on an IP-based line without a conventional analog or ISDN landline, do not plug in the end of the Y-shaped cable for landline. Otherwise, interference is transmitted to the FRITZ!Box:

  1. Check whether the black end of the Y-shaped cable is plugged in somewhere. If so, unplug the cable.

4 Checking the analog telephone line and devices

The following steps are only necessary if the FRITZ!Box is connected to an analog landline:

Connecting all telephones and telephony devices to the FRITZ!Box

  1. Connect all telephony devices (for example a telephone, fax) to the FRITZ!Box.

    Important:Connecting additional telephony devices or telephone sockets to the telephone jack can cause errors.

Testing whether another device is interfering with the FRITZ!Box

Interference from a device connected to the FRITZ!Box or the power mains may be reaching the FRITZ!Box. Therefore, perform the following test:

  1. Remove all devices and cables from the LAN ports and the USB port on the FRITZ!Box. If no devices are connected, connect a computer to a LAN port on the FRITZ!Box.
  2. If the error no longer occurs, then a device connected to the FRITZ!Box was transmitting interference to the FRITZ!Box or the computer now channels it off. Usually, you can eliminate the cause of the interference through one of these measures:
    1. Use a power strip to connect the FRITZ!Box and all other connected devices to the same electric outlet.
    2. Test different electric outlets and power outlet strips.
    3. Use UTP network cables to connect devices to the LAN ports on the FRITZ!Box. In contrast to STP network cables, for example the one included with delivery, UTP network cables do not have a ground wire and do not transmit interference to the FRITZ!Box.

      Important:If the problem occurs with a FRITZ!Powerline adapter, use the UTP network cable included with the FRITZ!Powerline adapter.

    4. If a device connected to the USB port is transmitting interference to the FRITZ!Box, do not connect the device to the FRITZ!Box. Instead, connect it to a USB port on your computer.

Signal quality is too low

If telephones connected to the FRITZ!Box continue to ring although there is no incoming call, then the signal quality of your analog landline is too low.

Compared to simple telephones, PBXs always place higher requirements on the signal quality of analog telephone lines. The FRITZ!Box clearly surpasses the limitation of the specifications to correctly identify and process incoming signals. However, in the case of extremely interference-prone lines, the FRITZ!Box's tolerance to errors can be slightly lower than that of an analog telephone connected directly to your line.