Kenwood Bluetooth Firmware updater tools KDC-BT645U

Kenwood Bluetooth Firmware updater tools KDC-BT645U REV 3.06 Bluetooth.
I am trying to connect a iPhone 12 Via Bluetooth.
It seems to connect the Phone / Contacts etc.

But i cant seem to send audio.

Does anybody know if that is a function on this model.

I have a Sony that does it...
It seems odd to me that a High endish, Head unit that has bluetooth, cant receive audio to play music.

I have found there are updates for the Kenwood firmware in a File format that does not seem to be recognized in the Firmware updater app. Setup_OEM
te0916k.krm
kdc-bt645u_fw_y400.ulp

Any Ideas?

Thanks