What's wrong with my speaker?

If you are thinking of saving a bit of money by trying to repair it instead of replacing the driver you are mistaken.

@kenjit No not at all. I was only hoping that it was a stabilization issue and not a problem with the driver itself. I've heard tell of people adding foam etc. It's most likely not a wiring issue. I've checked all directly connected to the driver itself. All seem solid. It appears that you're implying that the driver is completely damaged. If that is the case, I'll write to Vienna Acoustics requesting the purchase of a replacement.

How loud? The beethovens with those smaller drivers in a small box will sound stressed above 96db

I measured the, ahem 7” woofers in my beethovens and I think actual cone size is 5.5”. I love them and will probably always have them but they aint head bangin speakers 

@steve59 I'm not exactly sure how loud. I don't have a decibel meter on hand. It's not enough to hurt the ears, but I tend to like my music a bit on the loud side. I do know that I do not experience the same thing on the other speaker, so it appears that the midrange composite on that one is definitely able to take the stress. I suppose a replacement purchase is in my future.