A:Answer Hi cnyankee,
Thanks for your inquiry. Yes, you can enable or disable the Speak-to-Chat function. You can use the touch sensor of the headphones or the Sony Headphones Connect app to turn on/off this function. Please refer to this link for more information:
https://helpguide.sony.net/mdr/wh1000xm4/v1/en/contents/TP0002754732.html
Regards,
-Ralph