I have two chargers, one 45W and the other 25W. I have had them for almost a year, but I noticed that they started to make a buzzing sound and also heat up, not excessively, but noticeably. The 45W charger had this issue before, but the buzzing was not as loud as now, and it eventually disappeared.
I want to know if this is normal. I don't want them to catch fire.
1. Issues at home with your power utility provider. Verify and check on other electronic and electrical appliances for similar behavior or sounds. If there are no additional issues, then the internal transformer and electronic on your charger is damaged. Stop using it, and throw it away...unless you wanted to do a "forensic analysis/autopsy" on the charger...my humble comment from an engineering standpoint.
