If you haven't yet seen it, here how the adaptive drive works -> https://drive.google.com/file/d/0B1e...ew?usp=sharing

In particular I feel you are after the active roll bar which are hydraulic and get pressurized by the same pump used by the power steering. It starts from page 46

Provided I've never done diagnostics on it, I'm not sure if driving straight over bumps is good indication of whether it functions or not since the oscillating motor engages primarily when lateral acceleration is measured. In other words: try to take a sharp turn and see what sorts of pressure readings you get.

The shocks in the adaptive drive are not controlled pneumatically. I believe they simply have a controller that changes the compression brake in the shock (it probably changes the routs through a smaller orifice which results in greater dampening brake). It's probably a pretty dummy device that it's either hard or soft (depending on whether you're in sport or comfort mode), but not modulated like the active roll bar is.

I did replaced my front active sway bar because it was seeping hydraulic fluid, but that's really all there was. I didn't notice any particular noise of sort.

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