just updated my infotainment system to version 1.0.13 maps update also.
The update processes is a real "rig-ma-rol". Lots of usb pen drive swapping, with fussy file systems.
In the end I just sat in the car with my laptop.
I can still see that the muting "feature" hasn't changed since the OS update.
There is definitely a loud "thump" as well when the siri integration button action disengages and the original audio source starts to play again. I hope over time this doesn't potentially blow the speakers or output amp of the headunit.