DTMF issues

[volenin]

Hi,

I've noticed that I've started to experience issues with DTMF recently. Not sure when did it start - prob. around a couple of months ago. Interestingly, this happens all the time when I'm calling the numbers in the 'free' zone, but outside of my local zone (i'm in 416, calling numbers in 613). IVRs don't recognize the keys being pressed at all. Haven't noticed this issues within my local zone though.

I've browsed the forum for similar issues and some ppl mention that there was some upgrades on the FPL server that require updating the SIP settings (specifically, the default codec needs to be switch to 711). Is this true? Can you pls let me know which settings to check to make the DTMF work?

I'm using Cisco SPA2102 ATA, haven't touch config settings for over a year now. DTMF used to work fine.

Thanks,

Vlad

[FONGO_kris]

No recent changes (Within the past 8 months) would have required the change of codecs, we have always used G729a is primary and G711u as the fall-back to lower the likelihood of congestion on our media gateways. Have you tried forcing InBand DTMF with G729a as the preferred codec? Also be sure to set the 'Use Preferred Codec Only:' field to 'No'.

[volenin]

Hmm, I'll check the settings once I'm home. Any other settings I should check that might impact DTMF functionality?

[FONGO_kris]

I suppose the payload type or packet size could have some affect on DTMF, make sure the RTP payload (In the SIP tab) is set to 101, I believe it is 97 by default, and that the 'RTP Packet Size' is set to 0.020 from it's default of 0.030.

[volenin]

Thanks, Kris. I'll make sure to check these settings.

Vlad

[volenin]

Ok, forcing InBand DTMF worked. Just to make sure I have the other setting defined correctly, can you clarify which RTP payload settign u r talking about? I only have 'SDP Payload Types', but there are quite a few of them:

2011-03-09 21h17_04.jpg

Thanks,

Vlad

[FONGO_steve]

Ok, forcing InBand DTMF worked. Just to make sure I have the other setting defined correctly, can you clarify which RTP payload settign u r talking about? I only have 'SDP Payload Types', but there are quite a few of them:

2011-03-09 21h17_04.jpg

Thanks,

Vlad

Looks good to me Vlad - the AVT/telephone-event payload is set at 101.