I need to implement AVSpeechUtterance rate change in range from 50% to 150% relative to normal speed with a step of 10%.
The problem is that I can't really find neither absolute, nor relative rate values to build on.
I do know that normal rate value is 0.5. But setting it to 0.6 at least doubles the speed.
Documentation mentions AVSpeechUtteranceMinimumSpeechRate and AVSpeechUtteranceMaximumSpeechRate, but I fail to understand how to make use of it since I can't even access it.
Any help is appreciated!