The phrase "steady hum" means a continuous and constant low sound, like the buzzing or humming of a machine or the consistent noise of people talking softly. Full definition
This effect can also be achieved by steady hums or noises, such as from fans or machinery. (lostgarden.com)
On a Tuesday evening just before dinnertime, retail expert Burt P. Flickinger III joins the steady hum of foot traffic at the Trader Joe's in Larchmont, N.Y. Because Trader Joe's won't give Fortune any information on its stores, Flickinger, of consulting firm Strategic Resource Group, has agreed to walk through a few suburban locales and offer feedback. (fortune.com)
First, of course, is the steady hum of Moore's Law... The second factor is greater demand, stemming from advanced graphics in gaming and, surprisingly, from the GPU - friendly proof - of - work algorithms found in some of today's leading cryptocurrencies, such as Ethereum.» (hacked.com)