So everything’s working great but noticed that sometimes and for no apparent reason while the vehicle is parked there’s a pop and hiss either from the front or rear and that end will drop ever so slightly, maybe 5/10mm, is this normal? As I said suspension working perfectly goes up and down when requested and never sags. Steve

2005 2.7 TDV6 HSE, ongoing project.
1998 Volvo V70 R auto FWD, Back on the road again.
1999 BMW Z3 (owned from new) garage queen.

have you just got out of car or shut a door?

If so, very normal as just self leveling doing its thing TDV8 now with extra grin factor thanks to Alive Tunning: Gone but not forgotten

Sometimes yes, other times it’s when I unlock the car. Today the car had been parked for a couple of hours I went out to do the recycling and the rear suspension done it.
Not too concerned as she’s running soo well at the moment, I’ve not had to put the code reader in for three weeks  Steve

2005 2.7 TDV6 HSE, ongoing project.
1998 Volvo V70 R auto FWD, Back on the road again.
1999 BMW Z3 (owned from new) garage queen.

Yes, it's normal. Mine does it on the rear about 10 seconds after locking when I park on my sloped driveway, facing downwards.

And three weeks - that must be a new record eh, Steve?!  Kev

MY2014 L405 RR Vogue SE 4.4 SDV8 in Corris Grey
MY2010 L320 RRS HSE 3.0 TDV6 in Stornoway Grey

Your not wrong Kev, there was a time I thought I might ware the socket out.  Steve

2005 2.7 TDV6 HSE, ongoing project.
1998 Volvo V70 R auto FWD, Back on the road again.
1999 BMW Z3 (owned from new) garage queen.