When in a call made over WiFi Calling (T-Mobile) the touch tone keypad when prompted do not register. After I turned off the option and called over Cellular they work again. Anyone experiencing this issue on T-Mobile or other carrier? Help!
iPhone 6s Plus, iOS 9.1
iPhone 6s, iOS9.1 - Called number using Siri, tried keypad during menu of call, no response. Disabled WiFi calling and tried again, with success.
Systems that use DTMF tones to navigate menus are often sensitive to variations in line quality and latency. I imagine the system you're trying to access might have problems with any VOIP phone (which is essentially what WiFi calling does). Might work, might not. There's not much that can be done about it. The biggest part of the problem is outside of your control and the carrier's control. The biggest part of the problem is the system you're trying to call in to.
iOS 9.1 in-call keypad not working WiFi Calling
