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One-way audio issue, DSP doesn't seem to be online

Hi there,


DSP seems to be an issue on a T1 PRI I'm implementing onsite here with a client, at least from what I can tell?

Timing is right, checked q921 and q931 debugs and I only seem to have issues on inbound audio but not outbound to the PRI. Region settings looks good, we use the same setup with other sites with PRIs, but this is our first 4000 series we're using for voice. I've attached some diags and info... what am I missing? I had to move the PDVM from the mainboard to the T1 because it was originally configured on the mainboard - but I'm kinda stumped here.


Any help is appreciated, I've removed some of the config for passwords and ACLs, we had an older 2921 using 12 FXO ports that we're moving to a single 4451 on a 12-channel PRI.


Another file

I see that you have Zone Based Firewall config. You need to add ZBF under the "Service-Engine" as well.

interface Service-Engine0/1/0
no ip address

Nipun Singh Raghav
"We cannot solve our problems with the same thinking we used when we created them"



I've tried adding this, but it didn't assist the issue even after resetting the gateway. I've also tried a power down and minute wait on it, power cycles, and reseating the T1 PVDMs, etc.


What is interesting is, if I call OUT from the station phone I seem to get two-way, if I call IN, I get one way audio from the station, but NOT the PSTN... DTMF tones DO pass, and I see received packets on the phone itself. It's rather strange.


Does anyone have any other additions views?


It seems like networking possibly but I've had two separate firewall/route-switch specialists peek at this and they also cannot find anything.


Next step will be testing a SIP trunk instead or opening a TAC case, but before that - I figured I'd bounce this for a few more forum opinions.



So you added the ZBF config and still having the issue ?
While on an active call can you collect -

show voip rtp connection
show sccp connection

Do the following as well -
show call active voice compact (make a note of the call ID)
show call active voice stats

show platform hardware qfp active feature sbc datapath call <call ID>
show voip fpi calls callID <call ID>

Nipun Singh Raghav
"We cannot solve our problems with the same thinking we used when we created them"
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