One problem related to manifold/header/muffler/tail pipe has been reported for the 2010 Toyota Prius. The most recently reported issues are listed below.
Loud rattle, shaking in motor area. Was found to be a head gasket leak. Using a lot of antifreeze and white smoke out the tail pipe. While idle or in motion and while gas engine is running. Started intermittently at first and very short, eg. For a second or two, then got louder, more often and lasted longer. This car has 230,000 miles. This same issue is happening on my 2011 Prius with 128,000 miles. I researched this and it is a common place with gen 3 Prius cars. I can no longer drive either one of my Prius cars safely.