I had the typical issue with the warp rotors it started at about 23000kms.
But along with the vibration there was a noise it almost sounds like a rubber super ball bouncing in the dash, I assumed that by changing the rotor it would resolve both issue.
So now the car is at 25000kms, I finally got around to replace the rotors but the noise is still there when I go over bumps. It’s really annoying. Adding to that when I had the car up on jacks to due the fronts rotors I notice that both front struts are leaking, the car only has 25000kms and struts are leaking, noise in front, warp rotors. That a good sign of things to come.

 

hhr brakes seem to have issues... thats what ive taken in from readin this site.. mine sqeek alot , hopefully they dont get any worse

 

I've had the dash noise when you go over washboard bumps from the time my hhr was new. Bouncing superball is perfect description. It was not that bad, but when you add the vibration from the warped rotors, sounds like the front end is falling off.