I have recently upgraded from an MPP combo to an M2P Flymore. The M2P produces significantly more noise than the MPP did.
I haven't tried the spare props that came in the flymore kit as they look the same...
Is this to be expected and are the stock props the quietest?
The Mavic Pro Platinum was introduced with a redesigned prop-set to make it quieter. Its 8331 props are even called 'Quiet' props.
The Mavic 2 Pro uses an evolution of DJI's 8331 prop design - so in theory, that's as quiet as you are going to get with DJI stock propellers.
There has been a bit of a mixed review of the Master Airscrew [MAS] prop-set for the M2P - but feedback is largely good. I use MAS props on my MPP exclusively, as they are quieter and more efficient than the DJI 8331's.
You can get MAS prop's through Amazon, and they are delivered from the EU Agent in Bulgaria.
Generally, the efficiency of MAS prop's means that they need a lower rpm to do the same work. It's the lower rpm that reduces the noise and pitch of the sound.