Edit: Was typing my reply at same time as your post.
There is a bug in 1.40.5 on ARMv7 based systems: New PMS Version 1.40.5.8854 stops running after some minutes on Synology DS215j
A workaround is to fall back to 1.40.4.
You must uninstall the current version then install the earlier version. Synology does not support direct fallback. See FAQ 8: Uninstalling PMS - Reverting to a previous version.
You can also disable View State syncing on your account. If you share libraries with others, they may have to disable it on their account as well.
