We have a strange issue and we need your opinion
Incoming calls or outgoing calls to PSTN have very bad quality.. We use PRI.Note that not all the calls have problem.Its some times and occasionally..
We have checked the controllers and are clear..where we have to look for that issue..
CUCM-GW via h323 -PSTN-via PRI
ITS 6 years implementation and the problem appeared now
What kind of "bad voice" ?
Is it echo like,or robotic voice,slow motion voice? what exactly?
I have faced with robotic voice when PSTN provider changed their station type without notice.
If you're sure no changes were made from your side,try to find out maybe provider did.
One time when you are on the call everyhting its ok , and one time you have one way audio
If you have multiple T1's/E1's, try to find whether the calls which are going on 1 single T1/E1 giving issue.
Place test calls and if you face audio issue on that call, go to the voice gateway and check on which Interface the call is going. This can be done by giving the command
show isdn active serial 0/0:23.
Then try to analyze and find that is that only 1 single T1/E1 is giving issue. This will help us to identify if there is any misbehaving T1/E1
Hi and thanks for your reply
If i issue the command
GW#show isdn active serial 0/0/0:23
ISDN Error: Illegal Interface Se0/0/0:23
Also if we have a misbehavibg E1 ISSUE then what steps we have to follow
The config looks very good to me
The H323 is bound to an interface so that eliminates the usual oneway transmission
You also say that the system has been in for quite some time and just
recently suffering this issue.
I think you need to take thisup with your ISDN service provider
You could have some dodgy chennels in your link at their mux end
One other thing to clarify.
Your router has 2 E1s
0/2/0 is maked as OLD is it still in service.
clear your counters - all interfaces
show controller E1 0/0/0 brief
Look to see if any errors are rising
Repeat for E1 0/2/0 - (If it is still in service)
show controller E1 0/2/0 brief
You have E1 PRI, so you have to give 15th channel instead of 23rd channel
show isdn active serial 0/0:15
If you see there is an issue on one single E1, then you have to chase the ISDN Provider to check
Hi to all
Thank you for your answers
My opinion is also that the problem is on ISP site
Then if we found that specific channels have problem then the only steps that we can do are to block (ISP must block) these channels?