DTMF Tone Delay Unity Express 8.6

[MRCobb]

Hello,

I am having a weird DTMF issue on CME 10.5 when calling into Unity Express Voice mail 8.6.7. When a user calls in to check voice mail or anything else that requires DTMF, I am getting a 1-2 second delay between when the button is pressed and when the tone is heard on the handset.  The buttons that are pressed go through but it is delayed. 

Anyone have any ideas what could be causing this?  All of the phones are 7841 SIP phones. 

Phones are configured similar to this:

voice register pool  28
 busy-trigger-per-button 4
 id mac 0008.2F1A.29EA
 type 7841
 number 1 dn 28
 dtmf-relay rtp-nte
 description x4132 Phn RM
 codec g711ulaw

Voice mail Dial-peer:

dial-peer voice 51 voip
 destination-pattern 409.$
 b2bua
 session protocol sipv2
 session target ipv4:172.29.32.2
 dtmf-relay sip-notify
 no dtmf-interworking
 codec g711ulaw
 no vad

[Manish Prasad]

Have you tried keeping same dtmf type under both the dial-peers ? Either rtp-nte or sip-notify .

[MRCobb]

Thank you very much for your reply.

I tried your suggestion and this did not fix the issues. I did find the following bug and this seems to be the issue with my phones.  As of today, I have upgraded the 7941 phones to the latest firmware available and still have the same issues.  I do also have 9951 Phones and they do not have this issue. 

CSCuj64649 - Sometimes DTMF for digits during VM has a delay