The iPods charge themselves through the USB cable, so they will only properly work on a USB port that has sufficient power. It seems that your iPod falls back to power safe mode after a few seconds because it is not being powered from the USB port to which it is connected.
Try connecting it to a powered USB hub and see what happens. Most internal PCI USB cards also give enough juice to their USB ports. Of course, you should also first try it with all available USB ports on your computer - try the ones at the back first; they usually are fully powered.
Try connecting it to a powered USB hub and see what happens. Most internal PCI USB cards also give enough juice to their USB ports. Of course, you should also first try it with all available USB ports on your computer - try the ones at the back first; they usually are fully powered.