Frame pacing issue while using 4K over HDMI?

I didn't really know which forum to put this in, because I don't know what the problem is exactly, but it seems like a lot of people here are using 4K TVs as monitors, so I apologize if it should go somewhere else. I'm just at a loss of what to do.

I recently got a 4K TV (Bravia 49X830C) and I thought I game with it using my 980Ti. I used both W8.1 and W10, with the newest sets of drivers (and the previous set for W8.1). No matter what game, every couple of seconds there is an odd hitch in the video while playing at 4K @ 60 FPS. I used a non-demanding game (multiple games, really), stayed in a tiny area and moved around in a circle to remove any variable I possibly could. The framerate counter was over 300 the whole time. I tried downsampling on my 1080P monitor (using 4K internal resolution) and the framerate was similar with no evidence of this happening. I tried various VSync settings. 1080P on the TV set works fine. I just don't think it's a traditional performance issue.

I don't really have any other equipment to test with and I'm not an expert about this stuff so I don't know if the HDMI on the card (which I have never used since I use DVI to the monitor) is bad, the TV (I used multiple inputs) has some timing issue, or what. I tried different cables (I have a bunch of those Amazon basics High Speed w/ Ethernet cables and the one that comes with the WiiU). I just figured maybe someone else has run into this.

I have a couple of days to take back the TV, but I quite like the TV, really. It's actually really great on the PS4.

Try a different, shorter HDMI cable. Not all cables can transmit at high speed.

Sorry, should have mentioned that these are only 2m (or 8ft?, don't remember which) long