System problem

Hi all, wonder if anyone can help me here. Was listening to my system last night at a pretty high volume level. I went to turn it down to shut it down for the night and when I hit the down volume button on the remote the system dropped in volume and went almost mono sounding. Both left and right sound the same. Like someone put heavy. heavy blankets over the speakers. I thought a tube had blown in my preamp so I replaced them with new spares and no difference. Today, I plugged my monoblocks directly into my DAC/streamer and the same thing so I’ve eliminated my preamp as the culprit. Any ideas? My system consists of Wilson Maxx 3’s, Classe CAM600 monoblocks, EAR 912 preamp and PS Audio Directstream with Bridge 2. I won’t mention my turntable setup as I wasn’t listening to it when this happened. All drivers in the speakers are working, there is just minimal and muffled sound. Any suggestions would be appreciated. Thank you
It is definitely possible to have blown the resistors in the Wilsons crossover unit, they truly are suspect when playing at high volume.
Dont ask me how I know......
But there is also plenty of web information on lots of similar occurences with blown resistors under similar circumstances.
I had to call Wilson to get the right value resistors for my speakers and just decided to order them right then even though not cheap.

Good luck.
Thank you everyone. uberwaltz you are right, I pulled the grilles off tonight, unplugged all of the electronics and it is the tweeters that are out. I have spare resistors in the accessory boxes that cam with the speakers so will change them out tomorrow night. I checked the spares with my meter tonight and they are all to spec. I will update once I replace them.
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High volume, both at the same time? Oscillation? but from where?

Transient shut down POP.

They sounded good then turned them off or down?

You know where it’s winding up? It’s a good thing there is protection there. Must be some expensive tweeters to use that kind of protection..Better safe than sorry with the ol tweets though...

I just spent almost 700.00 on a pair. There will be nothing but protection... I’m frugal..;-)