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low volume on FXO ports

I have a 1761 running 12.4(7) [upgraded from 12.3.(11)T] at a remote site. It has 3 FXO ports (2 VIC-2FXO cards) which go to the PSTN. The callManager is across the WAN. When someone makes a call to the remote site coming in on the FXO ports the volume is very low. Adjusting the input gain and output attenuation raised the volume for the person calling from the PSTN but did not change anything for the user at the site. Pulling out the cable from the FXO port and plugging it in to an analog phone, you get a good quality call. However, calling the remote site through the FXO ports and having someone transfer the call to the main site (across the WAN where Callmanager resides), the volume is normal. Any ideas what this might be? What debugs or output do I need to check this? Thanks.


Re: low volume on FXO ports


Have you ever tested by having somebody place a call FROM the PSTN to the VOIP IP Phone network, and then have the user on the VoIP LAN transfer the call to a user out in the PSTN. Hence you will then have 2 PSTN users talking to each other.....what are the

results? Low volume or not?

Can you verify that the users are not hearing static, which could further compound a low volume issue?

Has this voice connection ever worked in the past without these issues before the upgrade?

What is the highest value for input gain that you used?

MGCP or H323 ?

Which IP phone models and load are you using in the location where you get low volume?


Faint audio is heard in the speaker while using handset

show call active voice stats,

The i/o stats are in perspective to the voice-port.

show call active voice brief

sh call active voice (x 2 at 10 sec gap)

sh voip rtp conn

sh voice call sum

sh voice dsp

I believe this will be address better by TAC (check config, do more tests, check topology, etc)



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