What are these settings?
If you have only a regular TV attached (and no AVR or soundbar with surround decoders), “Audio device kind” should be set to “Basic”.
If you don’t see this drop-down selector, change the “Audio Device” away from “Auto select device” to the right HDMI port.
A lot. The proper desktop apps can decode almost every Video, Audio and subtitle format on their own, while the web browser only understands very few formats. So your server will be taxed with transcoding far more often when using the web app as a player.
If you can’t find any clue what happened to the desktop app, reset it by removing its data folder. See Plex for Windows won't run - #3 by OttoKerner
