DICE Electronics DICE interface for iPod Mini Cooper - Manual (Page 13)

If your vehicle has Digital Signal Processing (DSP), the purchase of a DICE DSP kit may be necessary.
To see if your vehicle has DSP look for a bare metal coax cable and a 3-pin connector. If you don't find a coax cable and find a
6-pin connector along with a 3-pin connector, your vehicle doesn't need this DSP kit.
DSP integration
Connector location
BMW 5 series and X5 BMW Z4 BMW X3
3-pin connector
DSP amplifier
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