I realised the sound came from the USB cable connection. I quickly unplugged the phone.
I smelled the tip of my cable, and smelled like it was burnt.
I was shocked because I never experienced something like this before.
I thought my USB cable was spoiled. However, when I used another cable to charge my phone, the same thing occurred.
The phone micro USB port got really hot and it was smelling like it was burnt. The phone bottom will get very hot when it is connected. It won't charge.
What is happening?
Btw I have not dropped it or done anything with the phone except for rooting and unlocking bootloader.