Lagging and unresponsive when using Serato (SR) Library

Bug Reports
1

Hi @Slak_Jaw! Adding my setup, though my symptoms seem related but possibly distinct from the original sort-by-Source crash:

Device Model: MacBook Pro, Apple M4 Max, 36GB RAM
OS version: macOS 15.7.7
djay version: Latest
Hardware/controllers used: RANE ONE, latest firmware/driver
Streaming services: Tidal, Apple Music, Beatport/Beatsource
Approx. songs in My Collection: 14,000+

What I’m seeing specifically: the crash happens when I’m using my Serato (SR) or Rekordbox (RB) libraries within djay. After roughly 30–60 minutes of use, the app starts lagging and then becomes fully unresponsive, at the same time my RANE ONE stops responding too. Force-quitting and relaunching works, but the app takes noticeably longer to start back up than a normal cold launch. Separately, certain individual tracks will crash/freeze playback immediately when selected.

Given it’s specifically tied to the Serato/Rekordbox library integration rather than djay’s native collection, wondering if this is a separate issue from the Source-sort crash, possibly related to how external library metadata gets parsed/cached over a session. With a 14k+ track library, this might also be a scaling issue that’s harder to reproduce with smaller collections.

1 Like
Crash when sorting Library by Source
4

Hi @Katazui, welcome to the Community! Your issue as described sounds like something different so I’ve moved it to its own topic. Thanks for the setup details and detailed issue description. I have several follow up questions to help me troubleshoot this issue further:

  1. Please confirm your actual djay version number from the djay settings.
  2. Does the session degradation happen with both Serato and Rekordbox libraries, or have you confirmed it with only one of them? If both, does one trigger it faster than the other?
  3. Have you tested a full 30–60 minute session using only djay’s native My Collection (no SR/RB source active in the sidebar)? Does the lag/freeze still occur?
  4. Are your Serato/Rekordbox tracks stored on the internal SSD, an external drive, or a mix of both? If external, what is the connection type (USB-C, Thunderbolt, etc.)?
  5. For the tracks that crash/freeze immediately on selection:
  • Do they come exclusively from the SR/RB library, or also from My Collection or streaming?
  • Is this behavior consistent for the same tracks across sessions (i.e., always those specific tracks), or does it happen randomly to different tracks each time?
  • Do those tracks have anything in common — file format (MP3, FLAC, WAV, AIFF), unusual tag data, very long/short duration, missing waveform analysis?
  • Does the freeze happen on track load or on playback start?
  1. Is the RANE ONE connected directly to the MacBook Pro, or through a USB hub? Does its loss of response happen simultaneously with the djay lag, or does one precede the other?
  2. Have you made any changes to djay’s default Audio Device Settings (Preferences → Audio)?
  3. Are you using a custom MIDI mapping for the RANE ONE, or the (built-in) djay mapping?
  4. When the session degradation occurs, are you actively loading or browsing streaming tracks (Tidal, Apple Music, Beatport/Beatsource), or working exclusively with local files at that point?
  5. When the freeze occurs, are any other applications running in the background (e.g., Serato DJ Pro, Rekordbox, browsers, cloud sync services like Dropbox or iCloud Drive)?
  6. Do you know approximately which djay version this started with, or has it been present as long as you’ve used the SR/RB integration?
  7. Are you using OneLibrary with a USB drive connected during your sessions?

Thanks!

1 Like
6

Thanks for the follow-up @Slak_Jaw! Answers below:

1. djay version: 5.6.5

2. SR vs RB: Confirmed with Serato. I assume Rekordbox behaves the same since both point to the same audio files on disk, but I haven’t isolated RB independently.

3. Native collection test: When using djay’s native My Collection exclusively, the issue still occurs, but specifically on tracks that were originally imported from Serato/Rekordbox. Even browsing from the djay Collection tab, if the track originated from SR/RB, it tends to be the problem track (long load times leading to freeze/crash). Tracks that were never part of an SR/RB library seem unaffected.

4. Storage: All files are on the internal SSD.

5. Tracks that crash on selection:

  • Exclusively tracks originating from SR/RB libraries, whether accessed via the SR/RB tab or djay’s own Collection. Occasionally djay will report the track as “missing,” and relaunching the app resolves it temporarily.

  • Happens consistently to the same SR/RB-origin tracks, roughly 40% of the time, the other 60% they load fine.

  • All files are MP3, WAV, or FLAC with proper metadata tagged for both Serato and Rekordbox.

  • The freeze happens on track load, not playback start. Once it freezes, both the RANE ONE and the Mac UI become fully unresponsive, the current deck keeps playing but nothing can be interacted with. Force quit is the only option, resulting in dead air.

6. RANE ONE connection: Connected directly to the MacBook Pro via DJ Tech Tools Chroma Cables, no hub. Never had connection issues prior to this.

7. Audio settings: No changes from default.

8. MIDI mapping: Custom mapping: replaced pitch bend with beat jumps on both decks, and replaced cue, slip, and cursor buttons with stems controls.

9. Streaming vs local during degradation: This only occurs with local files originating from SR/RB libraries. Streaming sources are not involved when the freeze happens.

10. Background apps: Safari (running PlayThis.Live, my DJ request app), SoundSwitch, and QuickTime Player (recording the set).

11. Version history: This issue only started with 5.6.5, did not experience it on prior versions.

12. OneLibrary: Not in use.

Hope this helps narrow it down, happy to provide crash logs or a screen recording if useful.

7

You’re welcome @Katazui. Thanks for answering my questions. This is very helpful information.

  1. Yes, please capture and share a screen recording of both issues
  2. Does the issue occur with SoundSwitch and QuickTime Player not running?

Finally, please collect a log output from Console.app on macOS while replicating the issue in djay.
NOTE: Make sure your user profile has Administrator Privileges.

  1. Open Console.app: It’s located in Applications>Utilities or simply type Console in the Spotlight search.
  2. Set Up Console: In the sidebar, select your Mac under “Devices.” Click “Start” in the toolbar to stream logs in real-time.
  3. Replicate the Issue: Open djay and perform the actions that trigger the issue. Note the exact time of the issue. Once the issue is reproduced, click “Pause” in the toolbar to pause logging.
  4. Filter djay Logs: In the Console search bar, type “djay” to filter logs related to the djay software.
  5. Copy the Logs: Shift select the relevant log entries, the press Command (⌘) + C to copy the log text to the clipboard.
  6. Save the Logs to a Text File: Open the TextEdit App, create a new document, then press Command (⌘) + V to paste the Logs. Now go to File>Save and name it something like “djay_console_log.txt”.
  7. Share with Support: Upload the .txt file to your Google Drive/Dropbox, enable sharing permissions, then share a link to the file here.
8

Hello! It’s been a week since my last reply. I’m going to consider this topic completed for now so I can focus on others. However, please feel free to respond and we can definitely revisit this. Thanks!