Steering column noise

I have a 2007 Honda Civic that has a noise coming from steering column. It’s sporadic - it can last a few miles or as much as 20 miles. Don’t know quite how to describe it - either like a teacup and saucer held by a cold, shaking person, or 2 electrical wires touching each other. It doesn’t happen in the morning when I drive to work (about 40 miles) It happens when I leave work after the car has been in a parking lot all day. The noise seems to happen more during the warm weather. It might start soon after I start the engine, or like today, it didn’t start until I drove about 15 miles. When I stop the car, the noise stops. Before, I could rap on the steering column to stop the noise temporarily, but after the dealer “packed” the column, this doesn’t work anymore. Dealer says they really can’t fix the noise if they don’t hear it.

Anyone have any ideas?