SPARK KNOCK PLEASE HELP

Hey guys, I need some help. I have a 99 tacoma 3.4 5vz-fe 5 speed manual. I get occasional spark knock usually 3rd 4th and 5th gear around 1/3rd throttle. I have tried the following: new fuel filter, clean MAF, seafoam thru the tank, premium fuel. So far the only thing that has worked is premium. But as soon as I put regular gas back in the knock will occasionally come back. It’s not super loud. I’m at a loss. Truck runs extremely strong otherwise. Does anyone have a solution to this issue? Or more ideas. Please help

 

Possible burnt valve. I'd be looking at a compression test as my next step.

 

Wouldn’t it be doing it all the time? Also wouldn’t it do it even with premium fuel if it was a valve?

 

Wouldn’t it more likely be carbon build up? Or clogged cat? Vacuum leak? Faulty knock sensor?

 

Combustion chamber cleaner

 

What’s the best product?

 

My 13 does that at times on 87, at 30-40 with a slight increase in throttle. Now running 89 gas and no ping that I've heard.

 

https://www.youtube.com/watch?v=v4FRqRvGCBs