I have a Nuvi 2555LM, about ten or so years old. Recently it has started rebooting itself at seemingly random times. Sometimes it will restart three or four times in quick succession before settling down and doing its job. I contacted Garmin and they said that because of the age, they didn't offer any support. Poking around on the internet, I found a suggestion to reformat the SD card. I tried reformatting then updated the maps but it still reboots on its own. Any suggestions?