2010 Subaru Forester banging noise

2010 Subaru Forester Loud mid rear location when in third gear

Huh? I can’t understand what you are asking. Please describe more fully.

When I drive forward from a stop, at about 30 mph (manual transmission) there is a loud metallic bang coming from under back seat area just right of middle. The clang happens only once until I once again resume from a stop.

Not sure if this is any clearer.

Much clearer! That sure sounds like a loose exhaust heat shield kind of noise. Odd that it should happen when it does. A look underneath and a wiggle while the car is jacked up should identify exactly the problem. Any good independent shop can handle this.