All recordings fail immediately: "There was a transcoder error". Help!

Live TV & DVR
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2

I’m seeing the following errors in your logs at the start of the log file you provided:

Jul 27, 2020 19:18:24.377 [0xb6f88970] WARN - [FFMPEG] - Error loading external lib: /config/Library/Application Support/Plex Media Server/Codecs/5f603a2-3204-linux-armv7hf_neon/libaac_latm_decoder.so: failed to map segment from shared object
Jul 27, 2020 19:18:24.377 [0xb6f88970] WARN - [FFMPEG] - Error loading external lib: /config/Library/Application Support/Plex Media Server/Codecs/5f603a2-3204-linux-armv7hf_neon/libhevc_decoder.so: failed to map segment from shared object
Jul 27, 2020 19:18:24.377 [0xb6f88970] WARN - [FFMPEG] - Error loading external lib: /config/Library/Application Support/Plex Media Server/Codecs/5f603a2-3204-linux-armv7hf_neon/libaac_encoder.so: failed to map segment from shared object
Jul 27, 2020 19:18:24.377 [0xb6f88970] WARN - [FFMPEG] - Error loading external lib: /config/Library/Application Support/Plex Media Server/Codecs/5f603a2-3204-linux-armv7hf_neon/libh264_decoder.so: failed to map segment from shared object
Jul 27, 2020 19:18:24.377 [0xb6f88970] WARN - [FFMPEG] - Error loading external lib: /config/Library/Application Support/Plex Media Server/Codecs/5f603a2-3204-linux-armv7hf_neon/liblibx264_encoder.so: failed to map segment from shared object
Jul 27, 2020 19:18:24.377 [0xb6f88970] WARN - [FFMPEG] - Error loading external lib: /config/Library/Application Support/Plex Media Server/Codecs/5f603a2-3204-linux-armv7hf_neon/libdca_decoder.so: failed to map segment from shared object
Jul 27, 2020 19:18:24.377 [0xb6f88970] WARN - [FFMPEG] - Error loading external lib: /config/Library/Application Support/Plex Media Server/Codecs/5f603a2-3204-linux-armv7hf_neon/libmpeg2video_decoder.so: failed to map segment from shared object
Jul 27, 2020 19:18:24.377 [0xb6f88970] WARN - [FFMPEG] - Error loading external lib: /config/Library/Application Support/Plex Media Server/Codecs/5f603a2-3204-linux-armv7hf_neon/libac3_decoder.so: failed to map segment from shared object

I see you are running Plex in a Docker container… I don’t use Docker for Plex, but I did a bit of quick googling and found this thread where another user was using Docker and OMV getting similar errors. Does your mountpoint in OMV have noexec set?