I'm using Waze on an iPhone 4S through a Toyota in-car stereo connecting via Bluetooth. I'm playing music through the car stereo from the iPhone at the same time. When Waze speaks, the music fades but Waze is much quieter than the music and I struggle to hear. I have the Prompts Volume set to full in Settings -> Sound. The quality of the Waze sound is also relatively poor, it sounds like an AM radio compared to the high quality sound of the music!
Is there something I can do to improve this or is it just the way it is?