G400P Issues

Hello,

I have a Elastix server that is version 2.4.0 with a G400P that has two modules and two AT&T SIM cards installed. We are currently using this server to provide office phones in an area that we can not get POTS lines. The issue I am having is that once the server is rebooted the call quality is fine. Within a day though, the calls that are sent through the GSM card will be impossible to hear at the site with the Elastix server. The other end can hear the call correctly but on the Elastix side, the calls are impossible to hear because of distortion. I tested the server at our Corporate office and never noticed the issue. However, when I was testing in house, I was using a bare Asterisk install with a newer version of the chan_extra module. I have tried scripting the server to disconnect and reconnect the GSM stack using the AT+CFUN command but this doesn't make a difference. I also tried adjusting some of the codecs on the server to see if this is the issue but it hasn't seemed to make a difference yet. Could this be a hardware issue considering rebooting the server fixes the issue? I am planning later in the week to move the system from Elastix to a bare Asterisk install to see if this would fix the issue but any assistance would be appreciated.

Versions:
Elastix Server Version: 2.4.0
Asterisk version: 1.8.20.0
DAHDI version: 2.6.1
libgsmat version: 2.0.3

Output from "gsm show span X" commands:

D-channel: 2
Status: Provisioned, Up, Active
Type: CPE
Manufacturer: Revision: MTK 0828
Model Name: Quectel_M20
Model IMEI: 861111003494385
Revision: M20R06A03N32
Network Name: 310410
Network Status: Registered (Home network)
Signal Quality (0,31): 17
SIM IMSI: 310410656094310
Event:1
State:GSM STATE READY


D-channel: 4
Status: Provisioned, Up, Active
Type: CPE
Manufacturer: Revision: MTK 0828
Model Name: Quectel_M20
Model IMEI: 861111003497966
Revision: M20R06A03N32
Network Name: 310410
Network Status: Registered (Home network)
Signal Quality (0,31): 18
SIM IMSI: 310410656094193
Event:1
State:GSM STATE READY


Thanks,
Tim Brewer
Systems Contracting Corporation

Hi,

Maybe it relate with the compatibility.
Please try to upgrade your version of asterisk,chan-extra,and dahdi in elastix.Keep it same with your asterisk in house.

If it still have some issues,please contact me when you available.My contact info be shown as below:

E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Skype: rick.zhu3
Gtalk: This email address is being protected from spambots. You need JavaScript enabled to view it.

Best Regards.

I have updated the Asterisk related packages and I am currently waiting to see if it makes a difference. I will post an update once I know.

Thanks,
Tim Brewer
Systems Contracting Corporation

I have swapped the entire Elastix server out with a bare Asterisk server running the following versions:

CentOS 6.5
Asterisk 1.8.15.0
DAHDI Complete 2.6.1
Chan_extra 2.0.7

When I loaded the chan_extra.so module into Asterisk I notice an immediate difference over the Elastix server. It could be the updated driver, the absence of two levels (Elastix and FreePBX) of interface, or the fact that CentOS 6 supports the driver better than CentOS 5 but regardless the signal quality has increased by 5 on both channels as shown below (Edit: I noticed that in the start of the thread that I was showing higher signal quality but the usual signal quality for the system was between 13 and 16). I believe this will help alleviate a good amount of my issues. I will post an update after a few weeks to let everyone know my progress. If nothing else, maybe this can help someone else troubleshoot the card. Thanks to rick.zhu for the advice.

Output from "gsm show span X" commands:

D-channel: 2
Status: Power on, Provisioned, Up, Active, Standard
Type: CPE
Manufacturer: Revision: MTK 0828
Model Name: Quectel_M20
Model IMEI: 861111003494385
Revision: M20R06A03N32
Network Name: 310410
Network Status: Registered (Home network)
Signal Quality (0,31): 20
SIM IMSI: 310410656094310
SIM SMS Center Number: +13123149810
Last event: D-Channel Up
State: READY
Last send AT: AT+CSQ\r\n
Last receive AT: \r\n+CSQN: 20, 0\r\n


D-channel: 4
Status: Power on, Provisioned, Up, Active, Standard
Type: CPE
Manufacturer: Revision: MTK 0828
Model Name: Quectel_M20
Model IMEI: 861111003497966
Revision: M20R06A03N32
Network Name: 310410
Network Status: Registered (Home network)
Signal Quality (0,31): 20
SIM IMSI: 310410656094193
SIM SMS Center Number: +13123149810
Last event: D-Channel Up
State: READY
Last send AT: AT+CSQ\r\n
Last receive AT: \r\n+CSQN: 20, 0\r\n

Thanks,
Tim Brewer
Systems Contracting Corporation

i] Last edited by tbrewer at 2014-1-20 22:41 [/i

I am still having issues with getting this to work. I have done packet captures on the network and everything seems right on the SIP packets. I have also swapped the server to a different PC, tried updating Asterisk, DAHDI, and the chan_extra driver and it still isn't working correctly. I have discovered that by stopping the Asterisk service, restarting the DAHDI service, then starting the Asterisk service, the audio will correct itself. I have a script in place that does this once an hour but it's still not stable enough in my opinion.

Thanks,
Tim Brewer
Systems Contracting Corporation