I use Windows 10 and although I have been using Lightroom since it came out I have never tried the Slideshow option. Today I tried to make a simple slideshow using just four images.
All was going well and the slideshow played okay. However as soon as I added an MP3 that was already on my hard disk (and plays) Lightroom crashed. It would not restart until I deleted the Lightroom catalog lock file. I repeated this and it crashed again.
I then removed the MP3 and exported the video as 720P and it played. The slideshow had been made with the quality setting at Highest but the video image quality was poor. I repeated the export using 1024 but the quality was still poor.
Such a shame that I will not be able to use this facility.
My LR is always up to date. I use a Nvidea Gforce 1060 graphics card that is qualified for use with LR. I see no need to disable the Use Graphics Processor. Instead of continuing with LR slideshow I have done what many others have done and bought dedicated slide show software which works perfectly. Very sad that Adobe has failed for years to fix problems with this slide show option.