i've the newest version of plex media server installed under Mac OS X 10.11.6
while i'm streaming to other devices my mac will regularly just go to sleep. of course the video will freeze and if i don't jump up, run to my mac and wake it up again, the connection will drop. if i'm fast enough, the video will continue.
while it often happens during watching a movie, it also happens sometimes just when i finished watching something. the mac will go to sleep so if i want to watch something else i need to wake the mac...
why does this happen? doesn't Plex stop the Mac properly from sleeping while its streaming? does someone know of any workarounds (that don't involve manually disabling sleep any time i want to use plex)?