DTMF Issues

Anyone know what would cause DTMF to not work? On our aastra phones, it works perfectly fine. It seems like its just something with Cisco phones. We use the SPA525G phones.

Running Asterisk 1.6

Has worked fine with my SPA525Gs up to, dtmf mode rfc2833.


I have a similar issue with one of my users. I have three SPA525G endpoints on our PBX, and only one of them is having DTMF issues. As it turns out, the one having the DTMF issues is at the latest firmware revision, while the others have not yet been upgraded.

Without having had the opportunity to test out things, I am going to step out on a limb and say that it is likely due to a firmware issue on the phone.

That being said, however, since this post pre-dates the latest firmware revision, it may be a different issue that caused the issues you’ve seen - unless the DTMF problem was fixed in a subsequent firmware revision, then somehow mistakenly re-introduced in this latest one.