Odd noise on Gordini 1.5dci

[Lilgem]

Any ideas what a whistling noise while car is running could be? Started up 20mins into my journey home tonight and didn’t change with speed. Had car just over a fortnight and never noticed it until this evening.
It went into the garage last week to have cambelt changed and was found to need a new suspension coil spring but no other major faults were picked up.

Any help/advice gratefully received!
I’ve got a video but typically can’t get it to upload!