Plex Error for Transcode - Disk Space

I just installed the iX app for Plex. Everything is working fine, except whenever I try to play something that needs to transcode I get the following error message:

Playback Error
Not enough disk space to convert this item.

Originally in the Plex Transcode Storage config I chose emptyDir and memory, since I have plenty of RAM. I tried with and without specifying a quota. I tried memory and disk. Nothing worked.

Next I tried hostPath set to /dev/shm like I have on a different server using TrueCharts. That didn’t work, either.

Finally I gave up and chose ixVolume, but… that doesn’t work either!!

Any ideas here why I can’t get this to work?