I'm on my 7th rear air suspension bag in 18 months - Why !?

Well looked-after 2006 Allroad 3.0 TDI.

Does anyone know what could cause a rear suspension airbag to burst (and I don't mean develop a slight leak)?

I have had a saga all around the car, but the front seems to be sorted by: New pipes, new compressor, new valve block, new Bilstein struts (after the originals and the Chinese ones failed).

So to the REAR !

- Original bags failed
- Replace with decent quality from Germany
- These failed
- Replace with better quality Dunlop ones
- One of these has failed
- Now that Bilstein make rear ones I'm ordering one of theirs.

MY QUESTION - is there anything that can cause over-pressure / pressure not switching off / imbalanced pressure etc that could cause a premature failure as it can't be a coincidence any more ?

Also replacing the rear pipes and might as well do the rear level sensor.

HELP?

Thanks for the sympathy !

What really frustrates me is that I can never get to 'root cause', despite it going into two different Audi VW specialists who check what they can and repair the fault at the time - one of these specialists has a top reputation for high quality Audi tuning & servicing.

My understanding is that this generation of air suspension is quite basic, so the fault diagnosis side is very limited - so there's no point in biting the bullet and taking it into an Audi dealer at £120 an hour to be told the airbag has blown... and ...?

The irony is that my Subaru Impreza has just turned 20 years old and despite it being 'a bit quick', it keeps on going from service to service.
Its had more use in the last year than the last 5 because of the Allroad !

Can anyone help me?

Garage can find nothing - faults checked, readings checked, lines and connectors checked, soap tested.

If they don't know then I am going to buy rear struts and see if that helps 'take the weight' off the air springs