Wireless CarPlay

Hi all,
Seeking help for a CarPlay issue on iPhone 15 Pro Max…
Got a new Toyota Yaris-all connects wirelessly with the phone and CarPlay works well. But recently, when I try to send a message, Siri will do the usual “What do you want to say to xxx?”, but cuts off after “What do you want…”, and sends a message (either setting for auto send or manual tried) saying “What do you want”!
In other words, it seems to pick up its own voice as the message.
I’ve tried re-pairing, hard reset etc. I’ve turned on - via Accessibility- that you have to say Hey Siri to interrupt requests…all to no avail.
Works flawlessly if I connect via cable.
Help :pray: