Hello,
Recently been running into some issues with doppler when using more recent versions of FMOD (2.03).
When using doppler on newer versions, physics enabled objects sound jittery. I have linked a video to demonstrate, mainly listen for the police sirens near the very end of the video. Sounds like the position that doppler uses is moving around really quickly causing that jitter despite the cars in-game looking fine.
This is an issue that has only appeared since trying to update FMOD to the latest version 2.03.11 but also slightly older version 2.03.09.
I initially thought it was to do with Unreal engine version as I initially encountered this issue when trying to update UE to 5.6 (which required an FMOD version update) however I’ve recently also tried updating FMOD on our current UE version 5.2 and have ran into the same issue.
I was previously referencing this post as the UE version causing this issue I dont know what my problem is - #3 by apfelbaum but possibly this isn’t the case as 5.2 with the updated FMOD also causes the problem while older versions of FMOD (2.02.18 specifically) seems fine.
If you guys can have a look into this that would be great, if you need anything else from me to help let me know 
Thanks,
Calum