Cracking Noise on ISDN Line BRI

[fimozo]

We have a CUCM that is using a cisco router gateway with the ISDN VWIC cards. We have this consistent cracking sound on calls. if call are made direct from the modems this sound is not there meaning the issue is on the router. anyone please advise. 

[Nithin Eluvathingal]

Can you share the show controller E1/T1 output ?

2.12.0.0

[fimozo]

thanks for the response

its a bri not pri so cannot show that command

[Nithin Eluvathingal]

Try a different line card and see it makes any difference.

2.12.0.0

[Scott Leport]

Hi, 

Not worked with BRI for a while, but issue sounded vaguely familiar. 

Can you check if the following commands are applied to your voice-port? If not, can you try them?

bearer-cap speech 
compand-type ulaw