Hi all, New to this site. I have an 04 A4 130 sport avant. I have the concert series single disc hu. I have only a cd,fm,am,rds button around the power/volume knob. Can I hook up an Ipod to this. I have read posts about hooking one up to the cd changer but since I have no changer button on the unit can I do it ?. If so which one ? and from where ?.