I think I may be looking at a new DISA valve for the 330, as I'm hearing the tell tale slight 'rattle' at idle from that area of the intake, plus the low rev throttle response isn't what I think it should be (despite doing the 10 second 'ignition on/off' reset procedure before the last time I drove it). Plus, when changing from 2nd to 3rd under full throttle acceleration (in either Sport or Manual mode), there's a slight flat spot as 3rd engages before the revs pick up again.
I'm going to remove it (this evening if I get time), and have a look at it for play in the valve and if the pins are loose. I'm fairly confident I'm going to find out it's this and have already budgeted for getting a new one (where I hope Harry Fairbairn on here will be able to sort me out).
Seems to be quite a common thing to have to replace by all accounts?