Play X2 through usb Tahoe radio

[drumz311]

I have a new 2011 Chevy Tahoe and I want to be able to control my phone (Droid X2) with my stereo/steering wheel. I have hooked up my iPod through the USB port in the car and it works fine but I would rather use my X2. I tried connecting the phone with the usb/charging cable the other night and the car radio says "unrecognizable device" after trying all of the different connection modes like: pc mode, usb mass storage, etc. Does anyone know of a fix for this or know what I am doing wrong? I think the car radio might need a firmware update but I would not know how to get one. If anyone has any tips on this that would be great!