the navigation system in my 2003 s60 is turning on an I get the message disc cannot be read. I have rebooted the system and still have had nosuccess. I can use my tom tom and get better navigation info, however because of the problem I would have to drive around with the the volvo system up at all times yet inoperable....it will not turn off with the current problem. One dealer tells me I can simply disconnect the system and another tells me that disabling the navigation system will cause more problems because it is fully integrated into the audio system. Does anyone have experience with this problem or have suggestions?