Why is my phone charger making a weird noise?

So two days ago my phone charger for my lg env worked fine. Then last night I went to plug my phone in and I noticed a weird buzzing sound coming and I realized my phone wasn't charging either. I took the charger out of the outlet and tried other ones and I get the same result. Why? Is it something with the charger? That's what I'm assuming and if so is there anything I can do to fix it or am I SOL? Haha