Sudden loud screeching sound from the built in speakers(Macbook Pro 13" 2017 without touch bar)

I was on Chrome looking at a Youtube video. I was listening to it fine with headphones in, at about 1/8 of the full volume. I pause the video, pull my headphones out of the port. I set it to a little lower than 1/8 of the full volume, and hit play on the Youtube video. A loud "very loud like someone cutting glass with a diamond" screeching sound comes from the built-in speakers(I am not talking about the small clicks the HD seems to be doing once in a while).

Quickly, I pause the video. Then I make sure the volume is at an appropriate volume again. I hit play. There it goes again!(I didn't have any other programs on)

A restart solved the problem, but I'm not sure I can trust that it is truly fixed. Is there any explanation for this incidence out there or any suggestions on what to do next?