@doylecb: is this here a bit similar to what you are experiencing? (check the short video in the thread entry linked below):
While it is perhaps a bit exaggerated in the video, I guess some clanking is unavoidable. But it is also a sound that you likely only hear when you play low, and when you hear noises directly from the bass that, however, never really come through the signal chain.
Of course, as you also mention, how the bass is set up clearly contributes to how pronounced this issue is.