Reminds me of an old (~8yr?) article about applying machine learning to hardware - and one of the tests was producing a chipset that could produce a certain out

Reminds me of an old (~8yr?) article about applying machine learning to hardware - and one of the tests was producing a chipset that could produce a certain output tone. ... it worked, but only in a specific area of the lab. When they looked at the layout, they discovered the ML system designed a circuit that picked up relevant nearby EM/radio noise as the source, so when the chip was moved - it broke. It produced a radio! :) Wish I could remember the article since it also mentioned unusual circuit designs that weren't directly connected to each other, but used some IC 'gotchas' in advantageous ways (albeit inconsistently) to reach the goal.