Default Audio volume output on SlimKat

On inears the output is quite alright but when connecting to a stereo/car stereo the output is terribly low compared to i.e. an old Ipod.

Is there an option/switch/setting to raise the sound output on SlimKat 4.4?
Samsung Galaxy S4 i9505, SlimKat Weekly 4265 with Xprivacy
Moto Defy/Bayer, CM11 Quarx 14-03-27 with Xprivacy

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