Summary

 

Troubleshooting choppy, garbled and out of sync audio issues in your DECT network can be a difficult task. The M85/M65 and M25 handsets have a diagnostic menu that helps to determine if there is a weak or inadequate RF/RSSI signal between the handset and the M700 or M300 Base unit.

 

Checking RSSI signal level

 

If you are experiencing audio issues you should check the RF/RSSI converage in the areas where you are experiencing the problems. First check the RSSI signal levels between the base stations and he handsets.

 

 

1. On the M65/M85, press the menu key ; on the M25, press the OK key . The main menu is shown on-screen.



2. Type *47* on the handset's keypad. 



3. The handset will detect all base stations within range and show their MAC addresses on the display (Fig. 1). If the handset has detected more than one base, compare them with the MAC address on the type label of your base station to identify and select the right one. 



Fig. 1 



Fig. 2 



Fig. 3



Fig. 4 



4. If necessary, scroll to the MAC address of your base station. The selected item is highlighted in blue and expands to also show the IP address of the base station (Fig. 2).



5. Press the function key underneath "Select" (Fig. 2). The selected base station's RFPI and RSSI are shown on the display (Fig. 3). ◦ RFPI: The Radio Fixed Part Identity is a unique identifier frequently transmitted by the base station. ◦ RSSI: The Radio Signal


Audio Loopback Testing 

 

You can also do audio loopback testing to see if the RF signal in those locations your have tested from is a contributing factor of the audio issues.

 

6. Press the green key to establish an audio loopback connection to the base station (Fig. 4). You can now speak into the microphone of the handset to hear the echo of your voice.


You can also try enabling RTP Collision Control on the base



rtp_collision_control                     


Description 

This setting controls whether the base checks for RTP collision. RTP collision means that the device is receiving RTP packages from more than one source address with same SSRC. Default Value: off

 

Conclusion 

 

Try performing the RSSI and Loopback tests on the affected handsets when the issue occurs and keep a log of the RSS levels and loopback results for Snom Support if you open a ticket. If coverage and RSSI is an issue, adding DECT repeaters to extend converge in your Network may be necessary. 

 

It is also recommended to have the latest stable release of firmware upgraded to the base stations and the handsets. It is also a good practice to gather the syslog and systems, calls, repeater, and DECT statistics and settings files from the Base Stations for further analysis If the RSSI levels and loopback testing proves inconclusive.