I've got the Hydractive III+ suspension. I've noticed recently some odd things (I should point out I rarely use Sport mode, all the observations below are in Normal mode):

(1) from Normal height, I used to press the 'down' button to lower it, the front would go down first followed by the rear and a diagram would show up in the driver's console indication the car was in the Low position. This would take about 4-5 seconds. Then pressing 'raise' would take the car up to Normal, again about 4-5 seconds and an indication on the console that the car was at Normal height. Now, however, when in Normal and pressing the 'down' button, whilst the front drops, nothing seems to happen at the rear, and no message comes up in the console indicating the Low position. I've waited as much as a minute for this to happen. At this point, I press the 'raise' button and immediately a message comes up saying the car is in Normal position - but the front hasn't budged so is still in Low. To get back to "true" Normal, I have to press 'raise' again to take it (successfully) to the Mid-High position, then lower it back to Normal. The car then drives/rides as normal.

(2) Driving just after Easter in France on good A roads (130 kph), the car would sometimes ride as if on the bump stops, i.e. every bump or undulation in the road would be felt with a little bump and a small upwards reaction. When I stopped and checked the height, it was clear that it was indeed low at both front and rear. I would press 'raise' which would take it up the Mid-High (so the car thought it had been in the Normal position), then lower it to Normal, and all was well....until it happened again adter an arbitrary number of Km. As the roads were very smooth (why can't ours be the same?) I started to ignore it and eventually the car would raise itself off the bump stops and the ride would be normal again. Then it would go down again....then it would go up again. Since getting back to the UK, I haven't noticed this behaviour but I normally drive short distances at usually less than 70mph so I'm wondering if it's speed-related.

(3) I have sensed that both in Normal and (just for reference) Sport mode, the ride has become softer and more bouncy. In fact, driving now in Sport mode is about the same as Normal used to be.

(4) Driving over some of the local speed humps (the metal variety designed to slow you down to walking pace) the front mudflaps are now hitting these.

Taking all these things into consideration, it seems obvious to me that there's a problem. If anyone with more knowledge than me of the C5 Mk III Hydractive suspension (so that would be everyone, probably) recognises the symptoms and more importantly the probable cause, I'd be very keen to hear. Nos. (1), (3) and (4) started happening about two months ago and my usual Citroen dealer is in denial about it. When (2) started happening, I insisted he get Citroen in to look at it. I'm taking the car in on Tuesday, it would be useful if I could give then some useful information on what the problem(s) might be.