How deadly is transformer hummm...


Hello Folks,

I recently collected a lightly used (less than 50 hours) Dennis Had - Inspire - "Fire-Bottle." Within some few days, I noticed a humm emerging from somewhere within the chassis of the unit. As the unit was sold in "perfect" condition, I found the humm startling. Mind you, I've discovered absolutely no evidence confirming the sound is compromised; I mostly hear the sound within a couple feet of the amp, when the surrounding environment is silent.

This amp truly is a work of art. Nevertheless, I am now dealing with this 'humm' sound. I bought an Emotiva CMX-2 as a way to deal with DC offset, and this has not impacted the situation to any detectable improvement. Perhaps there is a slight improvement, but negligible. What to do?? Should I just relax, shake it off, and assume the amp will live well, or a down-the-road transformer replacement will simply become part of my experience with this amp? Should I put pressure on the seller to "right" the situation? He claimed, as I asked him, that it was the quietest amp he's ever owned. His add boasted that the fire-bottle exceeded amps from Pass Labs, a Cherry Amp, and one other that escapes memory. The seller has presented all of his communication in the manner of friendly professional etiquette. 

Your thoughts are appreciated. 
listening99
@jea48 the amp is entirely quiet at the speaker drivers; the amp was probably humming within the chassis from the start, but I did not hear it until a few days in.

I bought the rubber washers, but further comments seem to indicate that tightening of the transformer screws is the first task. I will unplug the amp, remove the tubes, put on a pair of gloves and remove the bottom plate of the amp this evening, and then I will tighten things. I can look for clearance that might accept the new washers, but I don’t plan on adding those in yet...

@wolf_garcia made an observation about the possibility that the washers will not do well with transformer heat. @atmasphere indicated they likely won’t fit, so the washers will be left out until I’m clear I won’t make things worse in the long run.

Can I expect the components are pinned to the top of the chassis, Or affixed to the bottom plate, etc.? I will be careful and slow in removing things, but I’ll take any tips...
@listening99  It would be a good idea to check in with Mr. Had and see if he has any comments. From the outside the amp looks conventional construction. Remove all the tubes before you turn the amp over to prevent damage. Keep in mind though that you are on your own here- if this is at all intimidating, it might be best to bring it to a technician to do the work.
@atmasphere I have not been able to find a close up photo of the transformer mountings of this amp, however, I respect your opinion, and feel, it is quite unfortunate. As I have stated, I have done hundreds of these " mods ", and all for the better, in every way. This is an easy thing to do, with the possibility of using longer mounting bolts. Not all rubber is effected by heat in the same way ( engine hoses, auto tires, as an example, as they last a long time, and the transformers do not get as hot as some engine components....this, ime. @atmasphere ...have you, in your amplifier designs, ever tried decoupling of the power transformers from the chassis ? Remembering now, I also had a Krell amp, a long time ago, that had huge rubber shims between the transformer and the chassis. As far as I am concerned, it should be a part of any design....but, I am not an electrical engineer, nor product designer.....just a tweeker, listening, and looking, to improve things my ear / brain can detect, as improvements is sq. My latest acquisition, and project ( an original Edge M8 power amp, prior to Maker Audio ), was so resonant and vibration prone. I took the amp apart, isolated the huge toroid transformer ( a few layers of Peel and Seal ), isolated and damped the heat sinks ( these heat sinks were the most " ringing " I have ever encountered, not what I would expect from an amplifier that retailed for 5K ), damped the entire chassis, and changed out wiring and binding posts. Now, an incredible, music reproducing amplifier, to these ears. BTW.......looking at many other Dennis Had amplifier designs, it looks as though, these rubber washers, can be used.....based on photos. Anyhoo.......Be well.
Wanted to add, I hear most transformers, when I place my ear, against the chassis of amplifiers ( including this Edge unit ), but, I accept this, as they all make noise, as I indicated. As long as it is not amplified, through the system, out to the speakers ( headphones, if that is your thing ). 
@mrdecibel  We had some very large EI core transformers on our MA-2 amplifier. One of them made a bit of humming. That was fixed by isomeric mounting; after that it was dead silent. The trick is not allowing the transformer or its mounting hardware to contact the chassis directly; that appears to be really difficult to pull off with this particular mounting system.