Adjusting the volume from VoiceOver not supported

[nidza07]

Hello,
with VoiceOver enabled, it is possible to adjust the volume of the current synthesizer.

To do this, on iOS 18, two methods can be used, the first one might be easier for a sighted user not experienced with VoiceOver, on iOS 17, only one:

First method, iOS 18 only

Make sure VoiceOver is enabled, ESpeak is in use and go to settings/accessibility/VoiceOver/audio/Audio ducking.
You will have a VoiceOver speech volume slider. Decrease it, notice that the ESpeak volume does not change.
Only at 0 percent does the ESpeak volume go to its lowest value.

Second method, works on iOS 17

Go to VoiceOver settings/rotor and make sure volume is selected in the list of rotor items.
You will need to perform the gesture to change the active rotor item, this is rotating two fingers on the screen clockwise or counterclockwise, the active rotor item will be spoken. Find volume, and then swipe up or down with one finger to adjust.
The result is the same, VoiceOver's volume does not change.

Remarks

I realize that you can adjust the volume inside the ESpeak application, however, not supporting this inside VoiceOver breaks the audio ducking feature in iOS 18.
Audio ducking is a feature where VoiceOver can lower the volume of other media when it is speaking, or always. In iOS 18, this ducking feature allows you to choose how much louder should VoiceOver be compared to other media, and it is this feature that does not work with ESpeak.

If it's possible, it would be nice to resolve this.

Thanks.