looping on InvalidContentType
Silan attempts to re-analyze files that fail during the process and loops indefinitely.
All the details are here: http://dev.sourcefabric.org/browse/CC-5270
If silan encounters an error it will exit with a status other than zero; it will not loop by itself (It looks like that's your python's script's doing).
Could you please provide an audio file that causes the problem?
Note that silan can run indefinitely if it is analyzing a live-stream instead of a file.
This was an airtime issue that was fixed with https://github.com/LibreTime/libretime/commit/50d5685199866487de4148d1a56fb8d67ea26674 ages ago. I also remember a post about fixing it in the linked JIRA issue. While the issue is still in Airtime 2.5.x (the fix was only on saas-dev), most of the time silan works properly so I think you can close it.