SOLVED: Room boom

Great to hear you found something that worked for you.

I had the same issue with my KEF Reference 5’s on my oak, tongue and groove floor. I bought some Isoacoustics Gaia ones and they helped a lot, but I still had some issues.  I went to a company that makes granite countertops and had them cut a couple of pieces to a size that fit under the KEF’s and it solved 99% of the vibrations. 
 

It's interesting.  Going from an old entertainment center to a solid component rack made an obvious audible improvement!.

You can get those much cheaper on supplyhouse.com