Why do we hear dialing tones during calls?
For a while I noticed a problem on different phones while having conversations with different people, without the problem being linked to a certaing mobile model. During the calls you can hear the dialing distinctive tone, just like the other person would press dialing keys during the call.
First of all, it’s good to know that the dialing sound should be heard during calls only if we have speaker mode enabled on the phone, otherwise you shouldn’t hear sounds even if the other person is hitting keys.
Every time I heard the dialing sound durin a call I checked my phone to make sure the screen is off and the other person assured me she is not pressing any key and her screen is also off.
I even thought about the person who I talk with pressing the hard keys by mistake during the call (for old phones which have hard buttons) but all of them were using smartphones without physical buttons.
It’s a strange situation which puts us in awkward positions, we’re sure we don’t press any button and the other person is also sure he/she doesn’t press any key. If we don’t know this is a common problem, then we are tempted to blame the other for hearing those sounds.
After digging into this issue, it seems that this is a common problem encountered by many users, not only iPhone users but also Android phones users, the problem is not more present on some type of phones than on others.
We can exclude the following possibilities which could lead to hearing dialing pads being hit durning our calls:
- the other person uses an old phone with hard buttons and hits those keys by mistake;
- the other persons do not hold the phone to their ear as they should to cover the proximity sensor and the screen remaing on and unlocked;
- the other persons proximity sensor do not work, consequently keeping the screen on and unlocked;
- our calls are not listened by FBI/CIA so we can hear strange sounds; I know many of you think to this possibility but even if they would bug your phone to track your calls, they would make sure you won’t notice it;
- it’s not that old tone being heard after a minute passes present on some operators systems;
After discussing about this issue with a telecom engineer it seems that this problem is being caused by some network errors. Specifically, when someone talks and the sounds they make match certain frequencies, they trigger those dialing sounds we hear. In most cases, this problems are being caused by female voices which is at a higher intensity, which sometimes match the network’s frequency for triggering dialing tones. The “solution” is for that person to speak at a lower pitch.
It sound from sci-fi or comedy movies but it’s true. DTMF (dual-tone multi-frequency) talk-off represent those situations when the phones system recognizes the recorded sounds (most commonly, female voices) as being dialing tones. DTMF tones are emulated/regenerated by the providers and some people’s voices triggers the DTMF regeneration which leads to that dialing tone we often hear, identical to the sound of pressing a key.
DTMF talk-off problem is common not only on mobile networks (2G/3G/4G) but also on VoIP (internet telephony) networks.
Therefore, if you hear dialing tones during a call I suggest not starting an argument about this as most probably the problem being caused by the mobile network provider. For now, there isn’t a solution for this problems, the situation being dependent of the compatibility of the other persons voice pitch with the DTMF frequency of the phone provider.
Did you encounter this dialing sound during calls problem until now?