Prius V (Audio/Electronics) :: Phone Speakers Would Silence During Call And Charging

I recently bought a 2014 Prius v, and I love most things about it, but so far I absolutely despise the way the audio system interacts with my iPhone 4S.

-If I plug the phone into the USB to charge it, the phone speakers will get silenced, and all audio will get sent to the car speakers. This happens even if the car speakers are off, and in that case the phone just goes totally silent. This would not be such a big deal except...

-The car often decides that I am on a call, when I am not on a call, and I am depending on the phone for Google Maps turn by turn voice directions. The screen on the car shows me as being in a call and silences the phone's audio. Occasionally it will play a brief bit of audio that sounds like it was recorded from within the car. If I push the button to hang up on the call nothing happens, and I just have to find my way to my destination without any directions. Or if I have enough battery I can disconnect the USB cable and get there using voice directions played on the phone speaker.

-The same issue sometimes interrupts audio playback when streaming audio from the phone.

-If I answer a call while I have audio playing, the audio keeps playing, and there's no apparent way to turn it off using the car controls. The car's next song and previous song buttons quit working too, so I'm at the mercy of whatever was on the playlist.

-I have to turn the volume up incredibly high to hear people who call me. When I end the call, the car suddenly starts playing a song from my iTunes music at deafening volume, even if I was not playing music before the call started.