Radio Sound is incredible, while AUX connections are way too low

So i have a Toyota RAV4. When i turn on the radio, even low volume is crisp, with rich bass. When i plug in my phone/mp3 player etc via AUX cable, even at high volume, the quality goes down the drain. The bass, treble etc sound like its being suppressed. How can i make it sound like radio? Quality sound at low volumes?

plz help:frown: