Srry if it was answered before but
I just finished my project that required me to have a narrating voice on the slideshow
but after testing my LO file, it worked fine except for powerpoint…
I know that this might not be the answer you would like to have but it could be a simple workaround.
I now assume that you want to use PowerPoint because it runs on the PC at which you need to give your presentation.
I was always afraid of such a situation until the LibO Portable Version appear. If I cannot use my own PC with LibO, I use a Portable Version of LibO and run my presentation just from a USB stick.
A solution, where I guess the success rate is lower, is to try to fix the problem while always using ppt or pptx format.
As for PowerPoint and Impress compatibility please have a look here and also look at the included link to LibO documentation.