after getting in my cobalt and starting it up i turned on the radio and it worked for a second and then displayed the word "LOCK" on the screen. i have a base sedan with the base level radio. i had to restart the car to get it to work again. any ideas of why this happened?

 

https://www.cobaltss.net/forums/electronics-audio-video-49/radio-cd-lock-up-2832/

Has happened about 8 more times since then.
I don't really want to take it in because I don't want them starting my car 100 times, trying to get it to happen.

 

the only problem that i am having with my Cobalts' radio is it sounds like speakers are cutting out and the drivers side door rattles really bad. Since I've only had it a week, I am really reluctant to call the dealer to bitch about it.

Probably will anyway.