The first step would be to ensure that the fill level is correct. There is a post somewhere on this forum that speaks of cleaning out a small screen in the rear part of the valve body if such a problem happens on a 722.3xx like you have.

Adding magnets is pretty good practice.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)