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Maybe they could work on the quality of the service now! One of my largest pet peeves is that Skype quality is so poor that DTMF tones can't travel across inta

Maybe they could work on the quality of the service now! One of my largest pet peeves is that Skype quality is so poor that DTMF tones can't travel across intact. If you're using Skype and trying to enter an extension, good luck. This morning I tried to use Skype to access my voice mail without success. Customer support is also horrible. The standard response is that it is the customer's fault. Audio quality on Skype seems to be directly proportional to how old the device is. Nokia Maemo tablet? Great! Nokia N95, not so great. Windows, Android, Linux, Apple? Nuh uh.

jeffbarr 14y ago
> One of my largest pet peeves is that Skype quality is so poor that DTMF tones can't travel across intact I nearly threw my laptop across the room in frustration this morning due to this issue. I was trying to log in to a conference call. I think it took me 5 calls and 9 attempts.
ajtaylor 14y ago
Ahhh, that would explain the problems I had recently trying to join a conference call. It took me 4-5 times, trying varying amounts of time between presses, before the conference system let me in. Voice wise, I rarely have a problem - even doing Australia to east coast USA - apart from the slight delay in travelling half way around the world.
crazygringo 14y ago
Does anyone know the technical reason for DTMF tones having difficulty? Because the quality of a Skype call, for me, is so much higher than a cell phone or landline, why do the tones have a problem? Is it something about the codec?
- DanBC 14y ago
  (https://support.skype.com/en-us/faq/FA10292/Does-Skype-Connect-support-DTMF-signaling https://support.skype.com/en-us/faq/FA10292/Does-Skype-Conne...) (http://datatracker.ietf.org/doc/rfc2833/ http://datatracker.ietf.org/doc/rfc2833/) (http://datatracker.ietf.org/doc/rfc4733/ http://datatracker.ietf.org/doc/rfc4733/) (http://datatracker.ietf.org/doc/rfc4734/ http://datatracker.ietf.org/doc/rfc4734/) (https://lists.cs.columbia.edu/pipermail/sip-implementors/2007-June/016970.html https://lists.cs.columbia.edu/pipermail/sip-implementors/200...) > GK>> You are right that with in-band DTMF, you need to perform tone detection at RTP level which isn't exactly an ideal scenario. (http://www.voipmechanic.com/dtmf-issues.htm http://www.voipmechanic.com/dtmf-issues.htm) > In some VoIP routes a switch may be configured to detect in-band DTMF which is sent by the VoIP ATA, but then switches to an out of band RFC2833 DTMF required for an upstream provider. This upstream carrier then terminates the call to the PSTN, possibly to a voice mail system, which will require regeneration of the audible inband DTMF tones. The switch has to detect and remove the tone sent by the ATA from the audio stream because the upstream provider specified RFC2833 DTMF. At times the switch can't always completely remove the in-band DTMF tone which is a problem, because by the time it has detected the DTMF tone, it has already passed a short amount of it. This small amount of in-band tone along with the RFC2833 tone sent are both received by the far end voice mail system which will then register an error (problem), possibly an invalid mailbox or invalid password.

jeffbarr 14y ago

> One of my largest pet peeves is that Skype quality is so poor that DTMF tones can't travel across intact I nearly threw my laptop across the room in frustration this morning due to this issue. I was trying to log in to a conference call. I think it took me 5 calls and 9 attempts.

ajtaylor 14y ago

Ahhh, that would explain the problems I had recently trying to join a conference call. It took me 4-5 times, trying varying amounts of time between presses, before the conference system let me in. Voice wise, I rarely have a problem - even doing Australia to east coast USA - apart from the slight delay in travelling half way around the world.

crazygringo 14y ago

Does anyone know the technical reason for DTMF tones having difficulty? Because the quality of a Skype call, for me, is so much higher than a cell phone or landline, why do the tones have a problem? Is it something about the codec?

DanBC 14y ago
(https://support.skype.com/en-us/faq/FA10292/Does-Skype-Connect-support-DTMF-signaling https://support.skype.com/en-us/faq/FA10292/Does-Skype-Conne...) (http://datatracker.ietf.org/doc/rfc2833/ http://datatracker.ietf.org/doc/rfc2833/) (http://datatracker.ietf.org/doc/rfc4733/ http://datatracker.ietf.org/doc/rfc4733/) (http://datatracker.ietf.org/doc/rfc4734/ http://datatracker.ietf.org/doc/rfc4734/) (https://lists.cs.columbia.edu/pipermail/sip-implementors/2007-June/016970.html https://lists.cs.columbia.edu/pipermail/sip-implementors/200...) > GK>> You are right that with in-band DTMF, you need to perform tone detection at RTP level which isn't exactly an ideal scenario. (http://www.voipmechanic.com/dtmf-issues.htm http://www.voipmechanic.com/dtmf-issues.htm) > In some VoIP routes a switch may be configured to detect in-band DTMF which is sent by the VoIP ATA, but then switches to an out of band RFC2833 DTMF required for an upstream provider. This upstream carrier then terminates the call to the PSTN, possibly to a voice mail system, which will require regeneration of the audible inband DTMF tones. The switch has to detect and remove the tone sent by the ATA from the audio stream because the upstream provider specified RFC2833 DTMF. At times the switch can't always completely remove the in-band DTMF tone which is a problem, because by the time it has detected the DTMF tone, it has already passed a short amount of it. This small amount of in-band tone along with the RFC2833 tone sent are both received by the far end voice mail system which will then register an error (problem), possibly an invalid mailbox or invalid password.