This is a cheap module that brings to your modular system:
Radio
Mp3 player (from usb or memory card)
External stereo input (line level in - modular level out)
Non traditional noise source
Usb port... to plug a lamp, fan or whatever you need.
The output is modular level.
Available assembled and DIY
Bill Of Materials:
1 x Resistors Zero Ohm (jumper) - SMD 0603 (populate 5v if you have 5v rail, if not 12v)
2 x Resistors 100k - SMD 0603 (R1,R4)
2 x Resistors 33k - SMD 0603 (R2,R5)
2 x Resistors 100 Ohm - SMD 0603 (R3,R6)
2 x Capacitors 100nF - SMD 0603 (C1, C2)
1 x TL072 - SMD soic-8
2 x mini jack
1 x Male headers - 2x8 2,54 mm
1 x Car Radio Mp3 Player from ebay or Aliexpress
+12v
-12v
+5v
All components goes in the back of the panel, which is the pcb also
Low Coast has not voltage regulator, if you don't have +5v in your modular be sure to get a "12v tolerant" unit
Jacks need to be wired like this