Maybe if you swap the left and right speaker positions and see if the problem follows? That would help eliminate other factors and help prove it's the speaker itself.
4 responses Add your response
After you switched the position of the speakers open the cabinet to see if anything fell off the back of the driver(s) like the magnet, or crossover components, and etc. Make sure all components are tight and not dangling around inside. Also make sure the wires are snug and fitting properly on the crossover and post.
I received a speaker once where in shipping the magnet structure had fallen off the rear of the driver and hit the crossover causing many problems. I hope you didn't experience any cabinet damage. Good Luck!
I did both things. Switched left and right locations, and looking inside. Everything is intact inside, and switching positions helped me figure out what happened. I just put it in writing so that perhaps someone can benefit from this later.
-- During the day I had been trying for the first time some new headphones for my mp3 player. They were really bad and I think they left me with an extreme sensitivity to the sound of the tweeter. After a couple of days, the sensation is gone.
Thank you for your suggestions. So great to have this community of audio enthusiasts!