Yes... another post on rattle/creaks... 

but as there is soo many of these posts I figured someone might have had the same issue..

so im driving an ST-3, so the suspension is firmer than the other fiestas, so could be down to that...  but the car seems to have developed a creaking rattle coming from the rear, now I've had my dad drive it while I sat in the back to try and diagnose the sound and it seems to be coming from the parcel shelf/rear roof line..

ive applied felt tape to where the parcel shelf meets the boot plastic and to no avail, I've take my steering wheel lock out and placed that in the passenger footwell, no avail, the rest of my boot is made up of a pair of football boots, my work bag, a boot organiser with cloths and one or two bottles of product for the car and a couple of coats.. I've checked all these they didn't produce any rattle of the sort. 

I know it's a long shot but it sounds like a plastic creak. Any advice/experience would be appreciated. 

At the moment I'm turning the volume up on my stereo to drown the rattle out but starting to give myself headache! Ahah! 

Cheers.

Hopefully you've fixed the creak by now.... but in case not...... I've just spent 6 months trying to find source of a creak from the rear (at low speeds but with large suspension travel).... turns out it was the tailgate latch. Put a couple of turns of plastic insulation tape over the latching eye and the creak is gone.