Why won't my television work with my PS4 anymore?

So my tv worked with the PS4 for quite a while, up until a few months ago, when my boyfriend let his parents borrow it. He had gone over to use it, and when he turned it on the screen wouldn't give a clear picture, and it was giving off a clicking sound. We've tried two different HDMI cords, and plugged them into different HDMI ports, but all met with the same result. So, short of going and buying a new tv, I was hoping there was a way to fix it. We know it isn't something with the PS4, and the surround sound and dvd player work with the tv. It seems to be exclusive with the PS4.