I started to notice rattles on my TSX for like 2 weeks now and this morning I finally figured it out. Maybe this is not the same situation with your tsxs, but this is how mine worked out

The noise seem to always come from around my passagere side door, and I could never figure it out. Then I discovered it was the passanger seatbelt banging against the side. After I strapped in the passanger seat belt, all my rattles went away.

On a different note, I finally started reving my car, 6000+ rpm is soooooo adicting
i MUST FIGHT THE TEMPTATION
I reved it like 4 darys in a row

 

A few weeks ago, I did notice a funny new thumping noise which turned out to be the passenger seat belt. It was twisted so it wasn't hanging properly. Luckily I located the problem that same day before it made me grumpy.

Also, my advice:
DO NOT FIGHT THE 6000+ RPM TEMPTATION
Gas is cheap in the US and the TSX likes to play -- I've revved it like 180 days in a row