It's very common not to duplicate bottom bracket or stress related sounds on the stand - not enough stress. Very unlikely to be a spoke, as the wheels turn at a different rate than the cranks. How to test? Here's a start: Creaks, Clicks & Clunks. The one thing I would add that Sheldon's page leaves out is that sometimes contamination between mating parts can cause a problem, such as rust scale on the spindle flats or where the pedals meet the crank arm faces, or even grit under chainwheel bolts. It's always good practice to clean off both mating surfaces. I use a fine steel wool and then a rag.

You'll have an easier time diagnosing sounds by adopting a methodical approach, and referring to Sheldon's page rather than scrolling through a bunch of "this happened to me" posts.