C30 General : C30 intermittent squeak

[jpb1]

Hi all,

I have 2008 1.6D C30 with 94,000 miles.

I get a squeaking noise (sounds like it is in the engine bay), normally lasts around 1 or 2 seconds.

First noticed it in town, at low speeds, often when changing gears. However, it doesn't do it systematically when I lower the clutch and change gear. On some journeys it doesn't seem to do it much, and on others more.

One place it does it regularly, is on a long fairly steep uphill on the motorway which has a 50mph restriction. I have the car in cruise control, so little change in my revs / acceleration. That particular incline and speed seems to make this squeaking noise happen the multiple times up the hill.
(it almost feels like the car very slightly hesitates at the same time as the squeak).

An ideas/advise would be much appreciated.
Thanks,
JP