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
Fuses? Doesn't cost to look... No idea where they would be. There may be none at all or in every piece, in the chain?

Just an idea.. Have any information on amps, speakers, anything that's in the chain..Look for fuses, resets.. This cost no money....

The pre is a valve unit? He bi passed it and still has the problem.

Swap the source, too. cost no money, right?

I don’t understand the mono thing? "Mono sounding", either. Source?

Cable explosion, just kidding...RAT chewed threw at the same time. ;-)

Something need a connection cleaning, geez...Sorry running out here.

Oh Oh, you played Yoko, Ono and it broke you stuff...? Ya didn't do that did ya?

Sorry my new stent it giving me a burst of PURE clarity... Man I can think much better..

Don't forget your cables (IC & speaker). I bumped my XLR IC turning my (very small) phono preamp off/on. Must have done this a few times and cracked the solder connection in the IC. System started to sound funny and I finally tracked it to ICs. Swap in some different ones if you have on hand.
Thank you everyone, even oldhvymec, kidding!!! I’ll turn on and off tomorrow and will call Wilson to see if it’s their fuses. Sure those will be inexpensive! It’s strange because everything still plays it’s just low in volume even when turned up and there’s no clear sound, it just sounds dull...
Initially, it sounded like you may have blown a combination of the tweeter and/or the midrange resistor fuses in the speakers. But you say you can hear every driver. Then it can only be the power amps. Perhaps they throttle down when overdriven.
That's my thought right now, or the Directstream. When I plugged the Directstream directly into the amps, I used the monoblock interconnects, not the DAC ones and the same problem persisted. Will continue to troubleshoot!!!
About that turntable... did you play through it to eliminate the DAC as the culprit?
Today, I plugged my monoblocks directly into my DAC/streamer and the same thing so I’ve eliminated my preamp as the culprit.

I'd definitely check the tubes and fuses in the EAR 912.

I will play the TT tomorrow night to see if that's the problem or not, as for the EAR, I plugged the DAC directly into the amps bypassing the preamp and the problem was still there. Will update tomorrow
Check your speakers rsistors:
Section 4.9 – Resistors By removing the back cover on the lower midrange module of your MAXXs, you may gain access to the resistor plate (see Figure 17). These resistors serve several functions. Note: Only Wilson Audio replacement resistors should be used in your MAXXs. Changing the value or brand of resistor will have a deleterious affect on the sonic performance of your loudspeakers and may void your Wilson Audio Warranty.
You said that speakers were pushed, give them a check. If ok then your power amps have the issue.
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..;-)