Server Version#: 1.23.3.4707
Player Version#: 1.33.0.2444
Plex for Windows stopped playing sound. I tried uninstalling and reinstalling Plex for Windows. Plex for Windows appears to attempt to use the correct sound device.
Movies and TV shows played through the Plex Media Server in a browser play normally. I installed Plex Media Player and it also successfully plays movies and TV shows normally, with sound.
Check that the audio device which is selected there actually exists and has speakers connected.
If device type = HDMI is selected, verify that the device which is sitting at the end of the HDMI cable is actually able to decode all the audio formats which have been ticked.