Thanks Otto 
The only change that has been made in the last few months are, that I’ve changed the e-mail address on my Plex credentials.
I tried Check, Vacuum, Reindex and Repair. Everything passed no errors detected. This didn’t change anything though 
The Plex Media Server logs doesn’t really show any errors. Only the usual SQLite warn field/column warnings (debug is not enabled):
Dec 05, 2022 09:03:28.857 [0x7f87f4fa5b38] INFO - ./Plex Media Server
Dec 05, 2022 09:03:28.887 [0x7f87f876cad0] INFO - [CERT/OCSP] Successfully retrieved response from cache.
Dec 05, 2022 09:03:28.956 [0x7f87f876cad0] INFO - Running migrations. (EPG 0)
Dec 05, 2022 09:03:29.164 [0x7f87f876cad0] INFO - Running migrations. (EPG 0)
Dec 05, 2022 09:03:29.284 [0x7f87f2298b38] INFO - Preemptively preparing driver icr for GPU HD Graphics 500
Dec 05, 2022 09:03:29.596 [0x7f87f1d71b38] WARN - [MediaProviderManager] Unrecognized MediaProvider feature: availability
Dec 05, 2022 09:03:29.596 [0x7f87f1d71b38] WARN - [MediaProviderManager] Unrecognized MediaProvider feature: availability-platforms
Dec 05, 2022 09:03:29.602 [0x7f87f191cb38] WARN - [MediaProviderManager] Unrecognized MediaProvider feature: availability
Dec 05, 2022 09:03:29.602 [0x7f87f191cb38] WARN - [MediaProviderManager] Unrecognized MediaProvider feature: availability-platforms
Dec 05, 2022 09:03:34.952 [0x7f87f1313b38] INFO - SQLITE3:0x80000001, 283, recovered 843 frames from WAL file /share/CACHEDEV1_DATA/.qpkg/PlexMediaServer/Library/Plex Media Server/Plug-in Support/Databases/tv.plex.providers.epg.xmltv-dc2486e2-053c-4257-93dc-2021f45c6c63.db-wal
Dec 05, 2022 09:03:35.136 [0x7f87f1313b38] INFO - Running migrations. (EPG 1)
Dec 05, 2022 09:03:35.203 [0x7f87f876cad0] WARN - [DatabaseFixups] Held transaction for too long (/data/jenkins/server/3520991443/Library/MetadataCollection.cpp:481): 0.140000 seconds
Dec 05, 2022 09:03:35.319 [0x7f87f4b49b38] WARN - [EventSourceClient/pubsub/192.46.236.7:443] MyPlex: attempted a reachability check but we're not yet mapped.
Dec 05, 2022 09:03:35.746 [0x7f87f876cad0] WARN - [DatabaseFixups] Held transaction for too long (/data/jenkins/server/3520991443/Library/DatabaseFixups.cpp:358): 0.180000 seconds
Dec 05, 2022 09:03:35.746 [0x7f87efcaeb38] WARN - Took too long (0.150000 seconds) to start a transaction on /data/jenkins/server/3520991443/Plugins/PluginDatabaseState.cpp:189
Dec 05, 2022 09:03:35.746 [0x7f87efcaeb38] WARN - Transaction that was running was started on thread 0x7f87f876cad0 at /data/jenkins/server/3520991443/Library/DatabaseFixups.cpp:340
Dec 05, 2022 09:03:35.746 [0x7f87efcaeb38] INFO - Refreshing paths watched by LibraryUpdateManager
Dec 05, 2022 09:03:40.735 [0x7f87f02d8b38] WARN - PublicAddressManager: WAN IP is a private IP address
Dec 05, 2022 09:03:42.388 [0x7f87f08fab38] WARN - [HttpClient/HCl#22] HTTP error requesting GET http://192.168.1.65:80/discover.json (7, Couldn't connect to server) (Failed to connect to 192.168.1.65 port 80: Host is unreachable)
Dec 05, 2022 09:03:42.389 [0x7f87f1b1fb38] ERROR - DVR:Device: Error refreshing existing device device://tv.plex.grabbers.hdhomerun/14109029, marking as dead.
Dec 05, 2022 09:03:43.365 [0x7f87ed15eb38] INFO - [Req#32] AutoUpdate: no updates available
Dec 05, 2022 09:03:43.419 [0x7f87ef52fb38] INFO - [Req#38] AutoUpdate: no updates available
...................
Dec 05, 2022 09:08:36.011 [0x7f87f0d0ab38] WARN - [Req#4b8] QueryParser: Invalid field 'contentDirectoryID' found, ignoring.
Dec 05, 2022 09:08:36.011 [0x7f87f0d0ab38] WARN - [Req#4b8] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:08:36.014 [0x7f87ed564b38] WARN - [Req#4b9] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:08:36.014 [0x7f87ed564b38] WARN - [Req#4b9] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:08:36.014 [0x7f87ed564b38] WARN - [Req#4b9] QueryParser: Invalid field 'contentDirectoryID' found, ignoring.
Dec 05, 2022 09:08:36.164 [0x7f87f0b07b38] WARN - [Req#4ba] SLOW QUERY: It took 270.000000 ms to retrieve 99 items.
Dec 05, 2022 09:08:36.189 [0x7f87ed564b38] WARN - [Req#4b9] SLOW QUERY: It took 370.000000 ms to retrieve 50 items.
Dec 05, 2022 09:12:31.685 [0x7f87f1516b38] INFO - [Req#4e4] AutoUpdate: no updates available
Dec 05, 2022 09:12:32.615 [0x7f87f2298b38] WARN - [Req#4f5] QueryParser: Invalid field 'contentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:32.615 [0x7f87f2298b38] WARN - [Req#4f5] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:32.978 [0x7f87f2298b38] WARN - [Req#525] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:32.978 [0x7f87f2298b38] WARN - [Req#525] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:32.978 [0x7f87f2298b38] WARN - [Req#525] QueryParser: Invalid field 'contentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:33.127 [0x7f87f0f0db38] WARN - [Req#517] QueryParser: Invalid field 'contentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:33.128 [0x7f87f0f0db38] WARN - [Req#517] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:33.171 [0x7f87f1b1fb38] WARN - [Req#526] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:33.172 [0x7f87f1b1fb38] WARN - [Req#526] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:33.172 [0x7f87f1b1fb38] WARN - [Req#526] QueryParser: Invalid field 'contentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:33.711 [0x7f87f2298b38] WARN - [Req#535] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:33.711 [0x7f87f2298b38] WARN - [Req#535] QueryParser: Invalid field 'pinnedContentDirectoryID' found, ignoring.
Dec 05, 2022 09:12:33.711 [0x7f87f2298b38] WARN - [Req#535] QueryParser: Invalid field 'contentDirectoryID' found, ignoring.
Plex Crash Uploader logs:
Dec 05, 2022 09:03:30.880 [0x7fa07155eb38] INFO - Crash Uploader - Platform: Linux ServerUUID: [REDACTED] UserId: [REDACTED] Version: 1.30.0.6442-5070ad484
Dec 05, 2022 09:03:30.879 [0x7fa07320d808] ERROR - Too many crashdumps detected / retries disallowed!
