Interior Squeak!

Hi Guys my car has developed a very annoying rear squeak, from the rear. It could be the cup spoiler but not sure but it is the most annoying thing I've encountered. I'll attach a video from the inside ASAP only makes the noise in a straight line, checked all of the trim etc and can't see a problem, help please it's driving me insane.
 
Hi Guys my car has developed a very annoying rear squeak, from the rear. It could be the cup spoiler but not sure but it is the most annoying thing I've encountered. I'll attach a video from the inside ASAP only makes the noise in a straight line, checked all of the trim etc and can't see a problem, help please it's driving me insane.

could be your boot catch? might need adjusting.. mine was sqeaking a few weeks back!
 
Sorted it lads, after stopping three times on my journey back to Cardiff and in loading and we loading my boot several times etc etc finally sourced the problem to my cup spoiler being loose, two turns of an Allen key and it's sorted. I was ready to scream.