hey! yeah you do get use to the taking off at first when i got my crossfire i was like also either a mini burnout or a jittery start, i haven't experienced the chunk sound when rolling to the lights but i do know the Chrysler crossfire first gear can pop out of gear some times.

i had the same problem when i bought my crossfire the gear **** moved around and felt cheap i easily bought a aftermarket **** very easy to install, you can get a OEM Mercedes gear **** off ebay for about $100

as for the sound i always have music on lol but it may be the spoiler..?

hope you find a good price for one they are great cars.