Cisco 7920 Administration Guide - Page 194

Resolving Voice Quality and Roaming Problems Chapter 9 Troubleshooting the Cisco Wireless IP Phone 7920 Step 4 Step 5 From Cisco CallManager, select Device > Phone and verify that you have assigned the correct MAC address to this Cisco IP Phone. To determine the MAC address of a phone, see the "Viewing the Media Access Control Address" section on page 6-5. Power cycle the phone. Symptom: The Cisco Wireless IP Phone Has Audio Problems When users report that active phone calls have poor voice quality that includes choppy audio, static or gaps in audio, or no audio, you can use the following suggestions to identify the cause of the problem. These sections can assist you with the following symptoms: • No Audio During a Connected Call, page 9-14 • One-Way Audio During a Connected Call, page 9-14 No Audio During a Connected Call If you are not using release 2.0, then you must disable TKIP and MIC features on the access point. These features are only supported with release 2.0 on the Cisco Wireless IP Phone 7920. One-Way Audio During a Connected Call Use the following list to identify possible causes for the problem: • Check the access point to see that the transmit power setting matches the transmit power setting on the phone. One-way audio is common when the access point power setting is greater (100mW) than that of the phone (20mW). Cisco Wireless IP Phone 7920 Firmware Release 1.08 and later supports dynamic transmit power control (DTPC). The phone uses the transmit power that the access point advertises upon association. 9-14 Cisco Wireless IP Phone 7920 Administration Guide for Cisco CallManager Release 4.0 and 4.1 OL-7104-01