iOS Question speech rate different between iphone5 and iphone6

[John Woodsmall]

Before the speech rate TTS1.SpeechRate =0.15
now that makes a very slow slurred speech rate
but when i make it 0.5 (which is ok on the iphone6)
it is much too fast on the iphone5.

is there a way to make them the same?

 

[Erel]

What happens if you do not set the SpeechRate? The default value should be used.