Xm Sat For Fly Audio Navi Unit

[Finsfan_9]

Hello,

I'm going to get the Fly Audio Navi for my 2009 IS250. I was told by Automax that it does not support XM Sat through it unit, but I can plug an external Sat unit through the Aux and it will work. My question is that I already have XM Sat installed in my car ( through my headunit, no external unit ) and was wondering if all I have to do is plug an external Sat unit into the Aux and it will work or do I need to install new wiring and reciever? Has anyone done this?

Thanks,

Rob