Poor quality slideshow after exporting and watching in Windows Media Player

Hi, 

I just made a slideshow (with music) in Lightroom Classic.  I'm very satisfied with the quality of the photos while viewing the show in Lightroom.  I exported the Slideshow to my hard drive as a video and watched it via Windows Media Player (Windows 10) and the picture quality is very poor.  The images are noticeably less sharp.  I want to send the slideshow to family members, but not at this low quality.  I considered exporting it as a PDF rather than a video; however, then I can't export the music.  Any suggestions on how I can improve the viewing of the slideshow in Media Player?  

Thank you!

- Tara