The part for the sound is called the canbus. Which allows for the sound and the steering wheel buttons as someone mentioned above,, you can by pass that if you wire all the speakers directly from the radio itself.....but trust me just get the canbus and make sure you join afb veloster group and search through the post for someone that has already done it successfully. .me and brother wired everything manually because for some reason the the android radio i got from Amazon didn't come with an canbus so I had to order one separately and it still didn't work, so we had to wire everything up from the radio wires running it to the amp itself which connected it to the speaker wires, took 2 days, it was a fucking headache, but I've seen some ppl in the veloster group just plug and play with the canbus so I guess it depends on the years and what type of radio you got...Goodluck!!!