The radio in my car makes a loud buzzing sound. Anyone know where the amp is at. on 2005 Buick Rainier

Need some help. Do you know where the amp is located.I was going to try that. I did remove speakers to eliminate the buzzing sound I know to fix the radio I have to take out everything.Also the little radio in the back does work with headphones. Any help would be appreciated.

Asked by for the 2005 Buick Rainier