Hi all,. So after driving her to work everyday for nearly two weeks, last night on way home from work, I was stuck in slow moving traffic and could hear a loud knocking over my stereo!  I turned the stereo down and it was awful almost banging noise.  As I speed up the knocking gets less.  I looked at the car underneath and can't see anything out of place etc.  However, the garage did say when they initially looked her over for me that there was a bolt missing from my gearbox and they would put one back in when I next came in?!?  Surely it can't be that.  It does sound like it's right under the car rather than suspension and all the suspension looks ok.  I have no choice but to drive her today but will take it steady.  Thoughts?

It might be the rear gearbox mount often called the "dog bone mount" the rubber insert in them do deteriorate and cause loud banging noises, normally when coming on/off the accelerator

Maybe an exhauast mount has given in. The mount that sits above the rear axle on my car has actually broken off the pipe but the pipe is in good general condition. Without removing most of my system to weld it back, i have hose clamped it back on as a 'temporary' fix. Occasionally i have to tighten up a bit when it creates banging underneath. One day, one day.