Sometimes when I play music I get no audio. Usually there is no sound at all, including system click sounds. Other times there will be Roku click sounds but no audio from Plex only. Restarting the Roku fixes the problem every time, until after a while it happens again and have to reboot again.
I am running PMS 1.8.0, Plex 4.4 build 1 on Roku 7.7.0 build 4117-29 firmware on Roku Ultra connected via optical to receiver.