my pioneer avic f900bt is having some issues, the system hangs on "system startup in progress, please wait" with the nav, phone and AV source displayed in the background then 5 mins later restarts, then the same thing happens again and again and again, anyway you get my point. The menu options are available and seem to work i.e I can play music by clicking the AV option. I've tried downloading the test mode files but they aren't recognized, I think the SD card slot isn't being picked up, I've also gone into the service menu by holding down all the buttons, and updating the unit from there but I can't, is there any way to use the USB to do this?? or any other ideas, please, please help me, i need music.....