Buzzing noise next to boot speaker

[M44]

Hi,iv got a 2006 ML320 and it’s had a buzzing noise coming from the boot area,I took the cover off that reveals the first aid and the speaker and then the surround that that cover fits into,it reveals a foam covered unit that keeps buzzing at regular intervals and always the same short burst,I can hear it from the outside of the car when I put me head near the unit and it stops after maybe 3 buzzes when Iv locked the car,when I unlock the car it gives a longer buzz then goes back to the short buzz say every 10 seconds,it does have pipes like widow screen washer pipes rather than the pipes that are going into the top of the air suspension,could someone possibly shed some light on what I’m experiencing and and help to resolve it,I’m guessing The foam is because it’s inherently noisy but something doesn’t seem right,
Thanks.
Mark

 

[M44]

Hi,iv got a 2006 ML320 and it’s had a buzzing noise coming from the boot area,I took the cover off that reveals the first aid and the speaker and then the surround that that cover fits into,it reveals a foam covered unit that keeps buzzing at regular intervals and always View attachment 97690View attachment 97690 the same short burst,I can hear it from the outside of the car when I put me head near the unit and it stops after maybe 3 buzzes when Iv locked the car,when I unlock the car it gives a longer buzz then goes back to the short buzz say every 10 seconds,it does have pipes like widow screen washer pipes rather than the pipes that are going into the top of the air suspension,could someone possibly shed some light on what I’m experiencing and and help to resolve it,I’m guessing The foam is because it’s inherently noisy but something doesn’t seem right,
Thanks.
Mark

 

[M44]

Hi,Iv found out that it’s the seat pump valve so I think I must have a leak somewhere,is the pump Drawing air in from the environment rather than anything to do with the air suspension and pump.