3.Tonsillitis
A virus or bacteria on your tonsils (the oval-shaped tissue pads at the back of your throat) causes tonsillitis — and can lead to a scratchy, muffled voice. You’ll likely have other symptoms like a fever, swollen tonsils that look white, yellow, or red, and a sore throat that makes it hard to swallow.
4.Voice Stress
When you misuse your voice, it can do temporary damage your vocal cords. It could happen if you talk loudly for a long time, shout, belt out a song at the top of your lungs, or talk in a really high or really low voice. It should get better with time, rest, and lots of water.