Sony h.ear on 3 Mini Wireless Help Manual page 98

If the C (custom) button is set as the Google Assistant button, Siri cannot be activated using the C (custom) button. When
activating Siri, use the touch sensor control panel.
If the C (custom) button is set as the Amazon Alexa button, Siri cannot be activated using the C (custom) button. When activating
Siri, use the touch sensor control panel.
Siri cannot be activated when you say "Hey Siri" even when the iPhone's "Hey Siri" setting is on.
When using the voice assist function, your voice will be heard from the headset through the headset's microphone (Sidetone
function). In this case, ambient sounds or the sounds of the headset operation may be heard through the headset, but this is not
a malfunction.
Siri may not be activated depending on specifications of the smartphone or application version.
Siri does not work when connected to a device not compatible with the voice assist function.
5-007-463-21(1) Copyright 2019 Sony Corporation
98