Experia 5 phone app will not generate touch tone after recent update

[KarlSch]

after the most recent Android Update, my Experia 5 phone app will no longer generate touch tones when in a phone call. This makes it impossible to interact with IVR systems that require touch tones

[KarlSch]

after the most recent  Android Update, my Experia 5 phone app will no longer generate touch tones when in a phone call.  This makes it impossible to interact with IVR systems that require touch tones