Making and Receiving CallsIssue Possible Cause & Solution ReferenceI cannot make IP calls. • The IP line is not selected.→ Before dialling, confirm that "IP" is shown in theupper-right corner of the display. Press the centre functionbutton ([F2]) to change the line if necessary.page 32• The IP address was entered incorrectly.→ Confirm that you have entered the IP address of the otherparty correctly.page 33• The "Operation Mode" setting is not correct.→ Change the setting to "Peer to Peer" if you want tomake or receive peer to peer IP calls (i.e., calls made byspecifying the called party's IP address).→ Change the setting to "IP-PBX" if you want to make orreceive intercom and outside calls as a SIP extension ofthe connected PBX.→ When the setting is "USB Audio", you cannot make orreceive IP calls. Change the setting to "Peer to Peer"or "IP-PBX".page 28• Consult your system administrator. —I cannot make TEL calls. • The TEL line is not selected.→ Before dialling, confirm that "TEL" is shown in theupper-right corner of the display. Press the centre functionbutton ([F2]) to change the line if necessary.page 32• The unit is not set to make TEL calls.→ Make sure the "Line Selection" setting is set to "IP +TEL".page 25• The operation mode is set to "USB Audio".→ When the operation mode is set to "USB Audio", youcannot make or receive IP, TEL, PS or PC calls. Changethe setting to "Peer to Peer" or "IP-PBX".page 28• The dial mode setting is incorrect.→ Make sure that the dial mode matches the type oftelephone service you have (i.e., tone or pulse).page 25I cannot receive IP calls. • The "Operation Mode" setting is not correct.→ Change the setting to "Peer to Peer" if you want tomake or receive peer to peer IP calls (i.e., calls made byspecifying the called party's IP address).→ Change the setting to "IP-PBX" if you want to make orreceive intercom and outside calls as a SIP extension ofthe connected PBX.→ When the setting is "USB Audio", you cannot make orreceive IP calls. Change the setting to "Peer to Peer"or "IP-PBX".page 28Document Version 2010/02 Operating Instructions 65Troubleshooting