All interesting stuff..... had a set of new tires on new rims but sat for some time. The panel would shake/rattle/roll at different speeds. Had tires balanced at my friends shop and watched them do it. Still bouncy, bouncy. Although the tires "balanced" it became evident some were "out of round".
Next...took tires off, checked rims (all checked good) then put on a new set of tires. Problem solved.
Are your tires out of round. Shaped like a donut??
Would it be worth the cost to have them "trued".
Just adding to the conversation guys.