Engine at idle in neutral. If the squeak goes with just enough light pressure on the clutch pedal to only just start to disengage the clutch, and stays not squeaking all the way to fully disengaged but then returns as soon as the clutch pedal is fully released then it is possible that the squeak is related to the clutch tangs/fingers and the release bearing. With a release bearing just catching the clutch tangs then sometimes a sort of ringing can be set up as the tangs/fingers vibrate at high frequency, then with a bit more contact of the release bearing they are stopped from ringing. If it is that then there is no great problem. The ends of the tangs/fingers will wear slightly over many many miles - just a thought. PJB