So I bought this unit to get HD radio. got it installed in circuit city. But all my audio controls on the steering wheel dissapeared. I can't control any audio at all. Is there anything can be done? To get vol up/down, tune up/down to work.

I have altima 06 3.5

You have to buy a certain type of accessory that's made for JVC that connects the wires from the steering wheel to the JVC receiver

You have to get an interface so that your steering wheel control will talk to the stereo.
Crutchfield sells them for just about any situation. Give them a call at 888-955-6000 and tell them what you need. They'll hook you right up! They will even give you installation instructions in writing and talk you through it over the phone if you have problems.