While on call, typing a digit on dial pad doesn't make any sound Since my Samsung Duos phone was upgraded to Android 5.0.2, during a call, when I dial some digits on the numeric pad, there is no keypad tone heard. As a consequence, when an answering machine asks my choice like "press one", "press two", I just cannot provide any choice.

I tried pretty much all settings (dialing keypad tone, touch sounds), with no luck, I can't even imagine why disabling this feature.

Any suggestions?
It is good to know that the problem has been resolved. After my suggestions including "cheat code" did not fix the problem yesterday, I discussed this with a Samsung ROM developer. You may like to consider options based on this discussion.

Firstly, the tones which failed are DTMF tones. These are NOT


User configurable
Affected by app misbehaviour
Custom ROM developers also do not tinker with this as it is a deep feature and they don't need to tweak it for user benefit
Stock ROMs/ upgrades will NOT disable it


As to how this happened is a mystery, but there is always an annoying possibility, that this may occur again. You have three options


Do nothing: If it happens again you can try using these kind of apps (bunch of them on Play Store, Google for "DTMF") DTMF Tone Generator


Any of next two options recommended


Device not rooted


Take backup using Kies
Factory reset
Do firmware upgrade/restore using Kies
Restore data using Kies



Or see this for other ways of taking back up  Full Backup of non-rooted devices


Device rooted


Take  nandroid backup using custom recovery backup
Factory reset
Flash upgraded Stock ROM 


Can be downloaded from Sammobile after registration. Make sure you download the correct version and of your region
Flash stock using Odin


Restore data from nandroid backuo