Hacker News new | ask | show | jobs
by bsmith0 1834 days ago
It's probably coil whine? https://en.wikipedia.org/wiki/Electromagnetically_induced_ac...
1 comments

Usually it's inductor coils and transformers, occasionally it's ceramic capacitors (all grades other than NP0 are microphonic, SMD or not), both problems are common in switched-mode power supplies, for example, powering the calculator LCD. I've never seen a singing resistor, very unlikely.