I asked because most audio content in movies are processed and synthesised more than the meat you find in baloney. In some movies, the audio track is completed stripped from the footage and recreated in computers. And you know what happens when you have poor content and revealing speakers...

But from the sounds of it, the problem is consistent across all movies. I'd probably check your connections and soldering inside the speakers. A month ago, I had a poor connection with the horn tweeter. Low frequency pressure from the woofer caused the connection to vibrate which in turn introduced a buzz in the HF.

Gar.