You can go for an Alpine CD changer which reads MP3 CDs as well. What do you mean you have Premium sound, but no DSP?

X5s are only sold with standard sound (10 Hi-Fi speakers) or with the "Audiophile" system which is 10 Hi-Fi speakers plus 2 subs and DSP.

Perhaps you are from Europe, and thus your options don't match the offerings in North America?

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