Hello @Roonee,
Thank you for keeping the server online - we have reviewed the diagnostic logs and have a clear picture of what is happening.
The logs confirm your Roon Server is healthy and the NAS connection is stable. There are no I/O errors or SMB failures. The slowness is a performance issue, not a fault.
Finding 1 - The NAS directory scan is extremely slow and variable
This is the primary cause of the week-long scan. Every hour, Roon re-enumerates the full \\QNAP\Musik\MP3 tree to detect new or changed files. For a 300,000+ file share over SMB, the logs show this single operation taking anywhere from 21 minutes to 9.4 hours in different runs:
- 06/07 ~02:00 → scan finished in 9 hours 23 minutes
- 06/07 ~15:53 → scan finished in 4 hours 22 minutes
- 06/08 ~06:39 → scan finished in 5 hours 7 minutes
- 06/08 ~09:53 → scan finished in 27 minutes
Two back-to-back scans of exactly the same data differing by a factor of 12× points directly at the QNAP NAS itself - most likely HDD spindown (drives going to sleep between scans, then needing 10–15 seconds to spin up per directory access across thousands of folders) or the QNAP being busy with its own internal tasks (Cloud Backup, antivirus, File Station indexing, Download Station) competing for disk and CPU.
Action: In QNAP Storage Manager, please disable drive hibernation/sleep for the volume holding your music. Also check whether any QNAP-side tasks (Cloud Backup Station, antivirus, multimedia indexing) overlap with the hours Roon is scanning.
Finding 2 - Audio analysis has a backlog of ~332,000 tracks
At the time of log capture the audio analysis queue contained 332,810 tracks and was draining at approximately 10 tracks per minute. Each track requires Roon to stream the entire audio file from the NAS to compute loudness data:
- AAC tracks: 18–40 seconds each
- FLAC 16-bit: 11–44 seconds each
- WAV/FLAC 24-bit: 28–59 seconds each
Go to Settings → Library → Background Audio Analysis and set it to Fast (not Throttled - Throttled is intentionally slower). This allows analysis to run at full speed across more hours.
Finding 3 — File discovery is already complete
All ~328,000 files were already imported by the time the earliest available log was written (June 7, ~00:30). The “65% scanning” progress you were observing reflects audio analysis completion, not file discovery — the files themselves are all in Roon’s library.
Summary
The QNAP TS-451D2 is powered by an Intel Celeron J4025 launched at Q4’19 — a dual-core entry-level processor running at ~2.0 GHz. At 300,000+ files, the NAS CPU itself becomes the bottleneck: serving SMB directory enumeration at this scale requires processing tens of thousands of metadata requests, which can saturate a Celeron J4025 entirely — especially if QNAP’s own background services (multimedia indexing, Cloud Backup, Download Station) are competing for CPU time at the same moment. This explains why two consecutive scans of identical data can differ by a factor of 12×. I do not see how we can speed up this process from the Roon side.
Please let us know if you have any other questions or concerns regarding this matter.
