I have just had the same problem on my 2011 50,000 mile XFS without driving hard. It is obviously a regular fault as the replacement at over £200 was immediately ex stock. Worse still I purchased a used car warrantee but it is restricted to moving parts and those containing oil not air. Even worse the separate inlet (or outlet) had been replaced before but was not showing on the history. There is clearly a fault in the original manufacture as the split in the joint between the two halves opens only under pressure or with a knife inserted. Is this part still used on the new model? Paul