I am facing a strange issue.
When i made test call from 9951 phones to 3rd Party IVR system, phones restarted. But only 9951 phones.
If i check "MTP Required" field on IPPhone page, problem solved but this time 9951 phones could not make video calls
Do you have any idea about this?
Does the 9951 phone reset everytime you call the 3rd party IVR?
Is it affecting only one 9951 or all of them?
Are other phone models also affected when calling the 3rd party IVR?
At what stage of the call is the phone reset?
For video to work on 99XX series IP phones MTP needs to be unchecked on the them, so it explains why the video does not work when you check MTP on 9951.
Video side is clear, i got it.
Your answers are kindly below;
- yes all 9951 phones reset everytime i called IVR system
- it is only affected 9951 phones, we also have 8945 and 6945 phones but there is no problem on that types.
(the only SIP working phones are 9951 in our deployment)
- phones reset at the first a couple of seconds after IVR prompt start
If we capture packets on the phone, i have seen lots of RTP packets coming from CUBE router.
As you see, this packets are malformed and CUBE router is where we host MTPs, XCoders and CFBs.
On your CUBE do you allow sip to sip calls, sip to h323, h323 to sip and h323 to h323 under voice services voip?
As you can see here, yes we allow all call scenarios.
allow-connections h323 to h323
allow-connections h323 to sip
allow-connections sip to h323
allow-connections sip to sip
That's pretty weird behavior. What is the cucm version and firmware version running on 9951's? Will need to check for any existing defects or known issues, else this will need packet captures and debugs from the phone for a test call to troubleshoot further.
CUCM Version : 126.96.36.19900-28
9951 SW Release : sip9951.9-4-1-9
I laready have packet pactures, CUCM traces and console logs of a test calls btw.
Maybe a silly question again, do you have a transcoder configured on your CUBE gateway and is that registered to your CUCM and in the MRL that the 9951 phones uses as well as your GW on your CUCM?
Hi again Hermanus,
Yes, there is two different transoder configured on CUBE and it is registered to CUCM.
They are also reachable by 9951s and GWs.