An old lady goes to the doctor.
Old lady: Doctor, I keep farting but my farts are silent and odourless. In fact I have farted 20 times since I was in your office. Since my farts are noiseless and don’t smell, you’ve not noticed it.
Doctor: Here let me make a prescription for you. But these and take it and come back after a week.
After a week the old lady comes back.
Old lady: I don’t know what was in those pills you gave me doctor, but my farts though still silent, stink like hell!
Doctor: Excellent! Now that we’ve cleared up your sinuses, let’s work on your hearing.