One more troubleshooting step: Can we try re-indexing the library? I believe you can do this in the settings for the synology drive.
I've escalated the issue and it's being reviewed by the software team. As soon as there are any updates, I'll post here on the thread.
I have reindexed the media files on the NAS, but unfortunately noticed to late that an update of Synology Mediaserver (v1.7.1-2820) go installed in the meantime too, because .... yes !!! ... I can now stream to my Bose ST's from the NAS again. Still "unfortunately", because I can't tell if the re-indexing did the trick or if Synology fixed mediaserver after all after my contacts with them. Their release notes for the new version just say "Minor bug Fixes".
Anyway, my problem got fixed, but let me know if you want me to run the diagnostic logs again as that may still help you guys to figure out what has changed and with that info help others.
Excellent! Glad to hear that it's working! I know it's been a few weeks since you posted, so I'm hoping you're still enjoying music from your NAS drive?
If you would be so kind, it would be great if you could get a second set of logs and send those to me.
Yep, all of my Bose systems are still playing from the NAS without any problems.
I uploaded new logs to the dropbox link that was provided to me before.