My toilet bowl has suddenly started making noise. Every few minutes, it makes a clicking noise. The noise sounds kind of like a kernel of popcorn has popped. What could cause this and what can I do to fix it?

Thanks.:)

Mine made the same noise for months. I was the only one who ever heard it until one day my husband said that the toilet was making a funny noise. We just replaced the inside workings and it has been fine everysince. Good luck