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On a tangent: acoustic noise.

My HP 32SII made terrible resistor noises. Bzzzzzzz like some sort of bad tinnitus. I could also hear it on an HP 48G when I placed my ear up to it.

Wouldn't it be possible to use SMT resistors and pot them in silastic to quiet them down?

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It's probably coil whine? https://en.wikipedia.org/wiki/Electromagnetically_induced_ac...

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.

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