I just installed my x710BT into my car, I used the bypass: http://www.avic411.com/forum/viewtopic.php?t=17013 and I grounded the mute wire. My problem is that I can't seem to get into the navigation settings or the system settings. The buttons are greyed out and the same goes for my phone menu.

Any idea what is going on?

Do the bypass properly. Re-read the instructions for the bypass and your problem will be solved.