I am a member of a Gwrra motorcycle group CA1M and we use Garmin products to exchange routs we plane and ride..I have had a Garmin Zumo 660 for about 4 months. The first unit failed out of the box because it would not recognize the SD card. Garmin Tech Support tried for hours to resolve the problem. The 1st replacement would work for a while then shut off, it would recognize the SD card and play the mp3 files. When plugging the units into the computer, and having "My Computer" window open the Zumo and the SD card would show for a very brief moment then disappear. The 3rd Zumo 660 was new out of the box and functioned great for a couple months. Then last night when trying to load a route the Mapsource program couldn't find the Zumo. I checked the screen "My Computer" and neither the Zumo or the SD card was shown. After removing the SD card the computer would recognize the Zumo, but with the SD card installed in the Zumo the computer would show both the Zumo and the SD card Briefly and then the drives would disappear. WTF is going on!!!! Can't Garmin fix the problem without exchanging the unit? Has anyone else had this problem?