Setting a parameter on a Sound Cue from Blueprints more than once is not working. The first time a parameter is set works, but any following sets are ignored.
This is a regression and does not occur in 4.27.2.
Issues does not occur with MetaSounds.
1) Create a Sound Cue
2) Add a Wave Player node and connect to to a Continuous Modulator node. Connect that to the Output
3) Set a Sound Wave on the Wave Player. Set it to Looping
4) Open the Details parameter on the Continuous Modulator node and expand the Pitch Modulation Params section. Set the parameter name to Pitch.
6) Open up a level blueprint
7) On BeginPlay, set up your Sound Cue to Spawn and set the Float parameter to 0.0. Add a delay and then set it to 1.0
The sound plays pitched down for 2 second and then plays at normal speed
The sound plays pitched down indefinately.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-148618 in the post.