Phone Connectivity Troubleshooting

Common symptoms and resolution to phone connectivity to a PBX

1. URL Dial Disabled
1. Symptom: URL Dial Disabled Displayed on the phone when a call is placed and the caller gets fast busy
2. Cause: URL Dial Disabled will be displayed on a phone when a call is placed while the phone is not registered with the phone switch. Since the phone is configured to automatically register with the PBX, this event should only occur when there is a loss of Internet connectivity.
3. Resolution: Establish adequate Internet connectivity.
2. ADPT Displayed on Line Button Instead of Extension
1. Symptom: When a phone completes its boot cycle, the line display shows ADPT instead of the extension number of the line.
2. Cause: ADPT is displayed on the line when the device is in an unassigned state. This means that station assignment has not yet been performed on this device or this device was previously configured and has been removed. In this state, the device will register with the PBX, but it will not be able to place calls or receive.
3. Resolution: Phone needs to be assigned. Please contact support.
3. Phone Does Not Stop Rebooting
1. Symptom: When the phone is powered on, it repeatedly reboots.
1. No network
1. Cause: A phone will continually reboot when it does not have adequate Ethernet connectivity. If the phone is not properly connected to an Ethernet switch, it will not boot properly.
2. Resolution: Ensure the Ethernet cable is plugged into the correct port on the phone and that the other end of the cable is plugged into an active Ethernet port configured on the appropriate LAN or VLAN.
2. No DHCP
1. Cause: A phone will continually reboot when it is unable to obtain an IP address. All phones are configured to obtain an IP address automatically via DHCP. If the phone is unable to obtain an IP address, it will not boot properly.
2. Resolution: Ensure there is a DHCP server on the network where the phone is connected and there are adequate available IP addresses.
4. Echo on Calls
1. Symptom: One end of the calls hears echo when speaking into their phone.
2. Cause: The PBX network is equipped with echo cancellers that remove echo from calls at the network level. However, often echo is introduced into the call locally by an external headset attached to the phone. Some headsets will create echo when the volume is set too high.
3. Resolution: Verify that the echo is being caused by a headset by having calls placed with and without the headset. If the echo is being caused by the headset, determine if lowering the volume resolves the problem. If it does not, then remove the headset.
5. Poor Voice Quality on Calls
1. Symptom: Call participant hears choppy voice or is unable to hear the other end for a short period of time.
2. Cause: There is a problem with the Internet connection.
3. Resolution: This problem must be resolved by the Internet Service Provider. If it cannot be resolved, an alternate method of Internet access may be required for phone service.
6. No audio on one side of the call
1. Symptom: When a call connects, only one party is able to hear the other.
2. Cause: The firewall is interfering with the automatic phone voice traffic routing.
3. Resolution: Contact the firewall support team and ask them to look at SIP configuration settings. Frequently, disabling SIP ALG (Application Layer Gateway) on the firewall, addresses this issue.