I've had this same problem when I first started using a Ethernet cable in my PS4. I think you just need to wear it in a bit, like a pear of shoes, although in this situation you need to just use the Ethernet cord more often. I think to solve your problem just power on your PS4, eject the disc, power of your PS4, wait 30 seconds and unplug your power cord from the outlet and your PS4, tip up your PS4 so the face of the PS4 is facing downwards on the table top or whatever you are on with your PS4 and press firmly on your Ethernet button thing on the bottom of it and just pull on the cord until it releases. If that doesn't work I would contact Sony support or look on Google to see if people had similar problems. Hope I helped, good luck!

Scraaapy wrote So I unplugged my Ethernet cable from my PC and into my PS4 so I could download a game faster and now when I try to unplug the Ethernet cable from the PS4, it doesn't come out. The little clip is not broken. I've tried wiggling side to side, up and down and still nothing.. Can anyone help?

I had the same problem, all you have to do is put a little extra force on the Ethernet clip for it to come out.

As said above just pull quite firmly and it should come out if that doesn't work it may be a faulty Ethernet cable.