...or it could be the insanely loud fuel injectors! Sounds a bit typical, but if you hold a funnel to your ear and aim it at the fuel rail, in front of your valve cover--you'll probably hear it coming from there. But if you hear it louder over the valve cover, maybe the valves are a little loose and need adjusted.
I doubt its anything to worry about, I have the same issue it started or atleast I noticed it about a year ago when it started to get warm at 1st I thought it was the heat but it was a little after I had removed all the plastic guards but I ride my car hard and have had a few miss shifts but nothing extreme, others here have raised the redline past where I hit with a miss shift, so I thought about it and figured it was just the lack of sound deading, however, I made one a few months ago I redlined 3rd and miss shifted to 2nd and the needle was hard against the stop peg I had to have reved past 10,000 rpm the IMA light came on and the engine screamed and since then its been subjectively louder I say that because I cannot tell if it really is louder or my fear, I had reset the IMA light, kept a check on the oil and characteristics(such as power/noises/feel) of the car and so far no change everything seems fine, I had a long trip last month(3000+ miles) and camped in my car with it idling and she was perfect no issues
I feel mine was quieter than the video until that miss shift but now sounds the same, I always thought it was valve sound but couldn't tell for sure(the major reason for me to check the oil as if I broke a valve it would have metal fragments in it) but the oil is clean, not burnt and within specified levels with no new noises and performance issues if I broke a valve Id know by now
I have watched this thread for the "vets" to answer to be sure for myself and they have said what I had figured, so I'm commenting now in case your still worried
Also, Id like to add its also doubtful that the noise means you need a valve alignment, you still may need one, but the noise doesn't have to do with it I have the same noise and around 50k miles