Have had my S3 Sportback since July 2012 and it's started squeaking from rear passenger side when going over bumps (which is every road in Leeds). Not sure why. Recently I had my rear bumper replaced after someone hit me so not sure if the garage did something or if it is a coincidence?

Still under the Audi Approved warranty however they said they will charge me to look at the car if it is not covered by the warranty. Are there any others who have had this and what could it be?

Also my brakes have started to squeak to but after reading on the forums, this may be down to the cold weather.