There's only one way to connect your phone to the A30 via the Hiby FC3. Since the FC3 is a DAC, it puts out an analog music signal from its 3.5mm phono jack. The A30 doesn't have a 3.5mm "aux in" port, so you will need a 3.5mm to dual-RCA cable or adapter. Or you can set the FC3 aside, and connect your phone directly to the A30's USB port with an appropriate cable. There is a micro-USB port on the back of the A30, so depending on the age of your cable collection you might need an adapter here as well. But in any case, with the A30's USB port you'd be using the A30's own internal DAC chip.
Which is the best way, with the lowest noise? You could find the specs and identify the exact DAC chips in the 2 devices, and probably find people on the web discussing the differences. But since it seems like you already own the FC3, why not just try it both ways and see which one you like best with your preferred music, your speakers/headphones, your room, your ears.
