2016 Toyota Highlander Limited - Radio reboots itself for no known reason??
From what I have read this seems like a problem a lot of Toyota owners are having. check with the dealer. I believe there is a software update for this. you might be able to go to Toyota’s website and get the software update from their and instructions how to install it.
also, some have said by turning off the Bluetooth on your phone solved the problem for them, but I am not sure if it will really work. I guess it is worth a shot.