I was hoping someone could give me a few pointers on this problem on my 2005 STI

I recently replaced the suspension as it had the dreaded knocking sound and it now has BC coilovers and its made a hue difference to the handling and the knocking has gone.
Before i did this i ocassionally heard a sort of rubbery squeaking noise coming from the rear nearside of the car but only on the Motorway after doing 70 for 20 minutes or so and it seemed to stop when i slowed down again, and going to and from my garage up a dirt track i sometimes hear rattling from that side as well but not always

Now after fitting the coilovers it seems to happen a lot more quickly and i dont want to ignore it in case its a symptom of something worse. From reading on here can it be one of the following

Failing bush
Squeaky seatbelt mount
worn shockmount

Any help would be appreciated

 

Did you sort this?

 

Yes i did thanks, uprated the drop links and its gone now

All i have to do now is figure out why i get a grinding noise on my drivers side front when i am on half lock.

It only happened after i fitted new discs and pads