Volume level is set too high:
- Decrease the volume
Sound source is distorted:
- If the iPhone/iPod original sound source (MP3) is old or of poor quality, distortion and noise are easily noticed with high-power speakers. Try a different file from a trusted source such as iTunes.
- If you are using an external sound source like older generation of iPod or iPod Shuffle, try reducing the output volume on the device itself. Also try turning bass boost OFF.
EQ settings are too high. For example, if the treble is too high, the 3D effect may not sound as good:
- Lower EQ settings.