I just installed it today and would like to update the firmware to 4.0 if possible, but I'm having a real hard time getting any info directly related to that. I see plenty on updating to 3.0 just nothing about 4. Is it possible? Also, I wanted to try to get the latest US maps. I would greatly appreciate it if someone could point me in the right direction.

Also, is there any way to turn off the damn touch sounds for the whole unit?? That shit is driving me nuts...

Thanks in advanced!