I am not (repeat "not") a HVAC expert, but the HE furnace on my old house
was intolerably loud. I was able to cut the noise by half by gluing wood to
the ducts. It damped the vibrations significantly. It was still noisy, but
at least I could live with it.
The house is still there 12 years later, so it didn't start a fire!

The one I just put in my new house isn't bad at all; so obviously it isn't
"all" of them.