Whenever someone calls in to our company's Panasonic phone system with an Apple iPhone 3GS (not sure about any others) the DTFM tones for entering in an extension to be transferred to play too long and so are not recognized by the phone system.
We have tested this with a multitude of other phones, land and cell and have not found any issues.
I know it has something to do with the iPhone Phone application or AT&T's service because I can call in over Skype with the same iPhone and be able to enter the extension and it is recognized.
Is there any way to change the length of DTMF tone output? Or get this fixed some how?
Unfortunately we are just end users like you. There is no setting to change this on the phone your going to need a update from apple on every iphone 3gs that uses the system if its a AT&T problem they may be able to fix it at network level. However the best way to get this out to apple is by submitting a bug report to there feedback system
There was an extensive user discussion of DTMF tone length and pauses in September and October of 2010. I was unable to respond to that thread because it is closed now, but is still accessible by archives.
AS many other iPhone users have stated in many forum messages, the iPhone 3, #G, #GS, and 4 all have a serious problem with DTMF tone length and speed. Some users on the forum have blamed ATT, but I never had this problem with other non-iPhone phones on ATT (or with Cingular before the buyout) and others are now having this problem now on Verizon as well.
The iPhone (3G, 3GS, and 4) all emit DTMF tones v e r y , v e r y slowly. So slowly in fact, that users often cannot use stings of stored access numbers, followed by access codes, followed by recipient phone number for international calling cards or business-related conference calls. The iPhone user frequently receives a voice error message from the calling card system stating that the access code is invalid, despite the correct number being stored, along with proper "," pauses. The DTMF tones are also sometimes too long, or too brief, and/or with inconsistent delays between the tones, creating errors in the DTMF data transmitted, hence the "invalid access code" or "incorrect phone number" being dialed. I was able to intermittently get the iPhone to work on international calling cards, by playing with the number of pauses "," inserted between access phone numbers, access codes, and recipient numbers, but success was infrequent and not consistent. Then I updated to the most recent firmware version for my iPhone 3G this past weekend, and now the problem is even worse: the tones sound weaker, sound more computer-generated (like a bad wav file of what was supposed to be a DTMF tone), are shorter in tone duration usually, and occasionally with a few very long prolonged DTMF tones, like the iPhone is locking up for a moment during the tone generation. But the main change is that the slow sequence of generated tones is EVEN SLOWER with the new iPhone firmware update. A number string that my LG Env3 cranks out in 3 seconds takes about 30 or more seconds, with each tone separated from the next by painfully too much time intervals between them.
My Verizon LG Env3 always works in this function with international calling cards 100% of the time, with rapid-fire DTMF tones generated from my saved nnumber strings from the contact list and no errors.
These very slow iPhone DTMF tones are not apparent to the casual user, because when numbers are entered manually, you do not hear the tones. However, when a string of tones is necessary to interface with an international calling card or to enter or set up a conference call, the very slow tones are heard in the earpiece and are 5 - 10 times slower than with any other "real" cell phone. ALL other phones by LG, Motorola, Nokia, etc. that I have used for these purposes with ATT or Verizon always generate rapid-fire DTMF tones, even when evoked from the Contact List memory, even when a long string of access phone number, followed by access code and recipient phone number are used.
Why can't Apple get this right. The iPhone is a great iPod, camera, computer, PDA, and web browser. But this inherent defect makes it a very weak business phone. PLEASE fix this !! Apple has not addressed the problem with ANY updates, even the most recent one.
I found a temporary work-around with a free APP called, "Phonecard". It allows calling card or conference call access numbers and codes to be stored, then brings up the contact list, and sequences the numbers correctly. The DTMF tones are still slower than with any other phone, but at least it works using this APP.
Apple, if you follow this forum. This is a real problem, a glaring deficiency, and if you want my company's comtinued business in the future, please do something to correct the slow, weak, inadequate DTMF tone gererator in your iPhones. Otherwise, the Droid X and Droids Incredible seem to handle this task quite well.
Well.. just picked up my new iphone 5 - verizon- and the good old slow DTMF is back. Can't make calls using calling cards if I store the numbers.
After the intentional pauses or wait, the following string of numbers go out with 4 seconds pauses between each number. After the 3rd or 4th number the calling card system times out telling me I have the incorrect pin.... Apple is researching
3 years later and I am still having this issue with I-phone 5s and IOS 8.1.2. Has anyone figured out a work around to sending longer or shorter DTMF tones?
I am trying to access my home security system and when it phones me I can't get any keys to work, but when I phone it, it allows me to manipulate menus.
Can anyone think of a reason why this is happening?
I've not encountered problems using my 5s, but that is when I call into my office to access the voicemail system. There is nothing on the phone that can be changed as far as programming those tones or tone length. That is something you would have to address directly with Apple. You can use the Contact Us link at the bottom right of every one of the pages here.
I recently had this problem on my iPhone6 with my bank and my credit card company. My software version is current (IOS 9.0.2). I'm right next to my router and have a strong wifi signal. If the phone is making wifi calls, the tones weren't recognized, but if I was only connected to my carrier the tones worked. Then, I noticed that I had turned the setting on for my phone to function as a wi-fi hotspot. Once I toggled this to off, the tones worked even when the phone was on wifi. I don't know if this is a quirk or a security feature. But I definitely recommend checking into your wifi and/or hotspot settings.
