PS Audio BHK300 didn’t work this morning.

Sorry to hear of your issues. When you say that you checked "everything" did you physically remove each fuse and test it with the continuity function of a multi-meter or similar? Visual inspection is not reliable.

You could try this: 4826 Sterling Drive, Boulder, CO 80301 Troubleshooting
PH: 720.406.8946 support@psaudio.com www.psaudio.com 15-070-01-1
Rev A8
Troubleshooting
©2015 PS Audio Inc. All rights reserved.
® Owner’s Reference BHK Signature AmplifiersCheck to make sure power is going into the BHK and it is connected to a live source. Make sure the
rear panel master power switch is in the on position and the lights near the tubes are lit. Push the
front panel logo light and it should blink, then remain lit after 30 seconds. If it is lit, look to the rear of
the unit and see if the tubes are lit and glowing. If there still is no sound, check the preamplifier and its
connections to the BHK. Check the speaker cable connections to the speakers

I would also try shutting it down and unplugging it from the wall for 5 minutes.  Unlikely to help but worth a try.  I would have thought a blown tube, but in standby the tube is off so likely not that. 

@OP PS Audio specifically say to unplug the unit from the wall if it goes into protection mode and won't reset.

I am surprised, if there is an internal problem, that the blue on off light is not flashing.

Since you have changed the fuse - having done the above - if still no sound, I would recommend checking all the fuses again with continuity tester.

If one has blown again it suggests and internal fault is definitely present.

Sorry to hear of your dilemma, unfortunately I can’t offer any help. But I wanted to share an experience I had about 2 months ago. I have a pair of 55# tube mono blocs and one had a failure. I called customer support ( Rogue ) and was advised to ship it to them for diagnosis and repair. They recommend “ Pirate Ship “ to obtain shipping labels and insurance. Second I decided to send both amps for a checkup and found out that the “ Bridge Rectifiers “ in both were tired and needed TLC in addition to the issue I had noted. I apologize if I have insulted your intelligence, but just wanted to share my experience in case it might help you with your issue. Respectfully, Mike B. BTW you have a fabulous system. 

@viridian 

Yes. And I reversed the input cables, checked the source and preamp. 

@mattmiller 

They just got back to me today and are going to send me a RMA so I can send it in.

Jim, thank you, and best of luck for a speedy resolution.

@yoyoyaya 

When I replaced the fuse, the amp went through its warmup and the relay clicked, but nothing.  One thing I didn’t notice until later, is that the one amp I’d cold to the touch.  Seeing as they are in standby all the time,they should both be warm to the touch and this one isn’t.

@OP - Thanks and best of luck with your repair. Do let us know what PS Audio find when they check the amp.

@yoyoyaya 

Will do. They said it would be several weeks before they could look at it, so I’ll reply after that.

Do let us know what PS Audio find when they check the amp.

Do you have a backup amp, so you don’t go crazy?  

Thanks Curiousjim. It's always nice to know how things turn out. I'm especially fascinated because of the fact that the amp is powering up - though not warming up - but no flashing blue light to indicate a fault.

I blew one of my BHK 300's back in December.  Totally my fault, I apparently sent a massive static discharge through my system that also took out a couple of tubes in my preamp.  I'm grateful the BHK 300's protection mode stopped it from getting to my speakers.  Anyhow, the good thing about this experience is PS Audio was very good about repairing the amp at what I thought was a very reasonable price.  It took a few weeks because of Christmas but I was pleased with the overall experience.  Good luck with yours.