Nuvi2699 screen

Hi,

I hope someone can help me. I have just found out this weekend that the screen on my wife's Nuvi 2699 flickers constantly when plugged in to socket in the car. It will start off as bright as it is supposed to be, then a second later, it will go a little darker (but not dark), then a second later it goes back to normal brightness, then a second later it will go a little darker, then back to normal brightness and so on and so on.

I have tried a different cable but have the same problem.

Now, I could be wrong here but I seem to remember having the same problem with my Nuvi 2699 and contacting Garmin who directed me to a setting to stop the flickering, but I could be completely misremembering.

Does anyone else have this problem?

Any help would be much appreciated.