Hard to tell about noises at a distance. Before you condemn the chain be sure of your vacuum pump. They often come apart with serious consequences for the chain as the pieces fall through it.
I wouldn't drive it till its looked at if the noise is regular and apparent. Whether you would do the job has a lot to do with your confidence. The chain times the crank cam and pump. No room for error.
It is easy to remove the valve cover to inspect, but you probably won't know what to look for as most will be subjective. Good Luck.
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician