Ridiculously Slow Syncing in Engine DJ Desktop

  1. Prime 4+
    • Engine DJ OS 3.3
    • Crucial MX500 2TB 3D NAND SATA
      • 560MB/s
      • CT2000MX500SSD1
  2. ROG Strix
    • Windows 11 Pro
    • i9-12900H @ 2.5GHz
    • 32GB RAM

Why does it take over an hour to sync/transfer ~20 tracks to the Prime 4+? I get some new tracks and I want to play those tracks. I can transfer these tracks to any other USB 3.0 drive within seconds.

The database directory contains multiple files, but they only total up to 226MB, so it’s not like each time I Sync, it has to send over a 10GB file or anything silly like that.

It’s the start of a new year, so I’m placing these in a new Playlist, with very few other tracks, so it’s not like I’m adding 20 tracks to a playlist that already has 1000 tracks, which may cause some complication. To be clear, this wouldn’t be acceptable, but I’m trying to provide as many details as possible.

I’ve even “Run Cleanup” against the database on Engine DJ Desktop, which doesn’t seem to help in the slightest.

I’ve only Analyzed tracks on Engine DJ Desktop 3.1, 3.2 and 3.3. I’ve never had a pre-3.1 database.

So, why does it take an hour to transfer less than 1GB of tracks over USB3.0 to an internal SSD in the Prime 4+ using Engine DJ Desktop?

Are you using the supplied USB type B cable that comes with the devices?

I connect that cable from my MacBook Pro (using a USB-C dock to connect to the laptop) to a Prime 2 and im able to format my SSD and upload all 120gb of music in my collection to the SSD in half that time. Adding music to it takes seconds.

Have you also re-analysed all your music since the DB updates were done post version 2.0? it tells you the version of desktop on the loading screen as it starts up… if your SSD is still on the old DB it will create issues, so my advice is to analyse all your tracks again, then format the SSD and upload the collection onto it again, with everything on the latest version, and using that dedicated USB cable (if you no longer have it, buy one as its much faster than USB 3.0 speed)

I am using the included, blue, USB B cable that came with my Prime 4+. I’ve connected this directly to the machine’s USB port, without using any USB hubs or extensions, although I do have a 3.0 hub on my second USB port for other devices.

I updated Engine DJ OS and Engine DJ Desktop. I never re-Analyzed my library after that upgrade. I assumed that when updating Engine DJ Desktop, the database would be updated alongside the software update. That’s how every database or program that utilizes a database has worked for me in the past.

Something I’ve noticed is that this long wait is true even when I haven’t added any new tracks, I just Sync again after having Sync’d, and I still have to wait a very long time for the process to finish.

Thank you for making me aware that this could help w. this Syncing issue. I’ll give the re-Analyze a try and see if that helps speed up the Sync process in the future.

Edit: I think you mean if my database is a 2.0, specifically. My database has only ever been as low as 3.1, then I upgraded to 3.2 and now 3.3. I’ll still try, as I know most of the database was created with 3.2.

Let me find the release notes for you when the DB changed after 2.0, I think there has been a fairly major DB update since too (possible 3.0 or around that version).

You will lose your cue points etc but the end goal is worth it.

Edit: Head here and read the release notes for both 2.0 and 3.0 on the desktop software (you can see it by scrolling down)… it explains the DB changes.

1 Like

Thanks for the information.

Even after I Sync and the Prime 4+ is up-to-date, if I Sync again, it still takes an hour to finish Syncing. This seems super weird to me.

I’ve only ever had 3.1, 3.2 and 3.3. I’ve never had Engine DJ OS or Engine DJ Desktop less than 3.1. I am still going to try re-Analyzing all tracks now that I’m on 3.3, but it seems like your solution was for 2.0->3.0 databases specifically.

Oh yeah, if 3.1 is your earliest then don’t do that as it is a waste of time and effort… that sounds really weird, do you use other software like Rekordbox and how does that perform if so? The internal SSD number one advantage for me is how fast it imports music. That is why I have no issues formatting and redoing my whole collection, id never do that on a USB stick.

Just Engine DJ Desktop. I don’t have anything else installed. No iTunes, and all of those Integrations are turned off. The only other software I use is SoundSwitch. Engine DJ Desktop does export SoundSwitch files to the Prime 4+ SSD, but each of these files is 30-100KB, so when adding 20 tracks, this should be very negligible for the total time it takes.

Is your music stored internally on the computer too or are you sourcing it from an external drive? thats the only other obvious thing I can point to that will slow it down.

Oh and on Sync Manager does the space remaining look correct? in comparison to what your disk manager tells you.

I can copy these 20 tracks to any other USB 3.0 drive within seconds, when Engine DJ Desktop is not involved.

Last week, I deleted the Engine Library/Database2 on the Prime 4+, knowing it would take a long time to re-Sync fresh, but I thought it might help with this issue. So I spent a few hours letting it Sync to a fresh disc.

Unfortunately, I still experience this issue with Sync’ing taking forever, and again, even Sync’ing immediately after Sync’ing is taking over an hour to complete.

I did realize now that the Prime 4+ Music directory contains duplicates. I’ll just delete Engine Library, do a full Sync, and see if Syncs after that complete more rapidly.

if that does not work…

rebuild the laptop collection

It’s worth a go, format the SSD before you start too, I tend to do that to do a clean build, in fact it was only a few weeks back I did it again.

Is all you music stored on your PC hard drive? If its on an external it could be that causing the bottle neck.

I have an old HP X360 Win11, i5 8core 1ghz, 16gb ram is less efficient than your hardware, Engine Desktop takes between 33 and 35 minutes to export 91GB of music or 8917 tracks, meaning that an SD card will never be as fast as an SSD. As for an export in the P4 which has a Crucial MX500 500GB SSD or in the P4+ which has a Samsung 860 Pro series 512GB, the duration is between 9 and 17 minutes max. Maybe the 2TB version of the Crucial MX500 just isn’t good enough for writing, but it’s still strange given how few files you’re trying to export.

1 Like
  1. Erased Engine Library directory from the SSD
  2. Sync’d to Prime 4+
  3. Sync’d to Prime 4+ again (nothing added or changed)
    • Export to Drive warns files may be overwritten/deleted
    • Takes an 30m to complete

It’s so goofy to me that I could Sync to the Prime 4+, and without making any changes to Engine DJ Desktop, when I try to Sync again I’m warned that I may lose files. Not to mention I have to wait a minute after hitting Sync, even though I know I have to wait an hour, because this dialog box just always appears.

It’s also pretty breaking that after Sync’ing to the Prime 4+, and without making any changes to Engine DJ Desktop, it takes 30m to Sync again. Without adding any tracks. Just Sync’ing after a Sync.

Anybody know what checkTrackMediaFilesToCurrentDevice does? I mean, I can read the name of the function, but an actual understanding of what it is doing. Zero search results on the Internet, but I do see this function failing on some files. These files play just fine and look like all of my other working files, so I’m trying to understand.

[W] void __cdecl LibrarianController::updateCurrentCollectionController(void) Can not fetch current collection           [2024-01-17T16:42:51.006Z] [air.planck.database     ]
[W]  controller.                                                                                                         [2024-01-17T16:42:51.006Z] [air.planck.database     ]
[W] [ 0x23712e32e38 ] Job Failed "Clearing database" ""                                                                  [2024-01-17T16:42:51.062Z] [air.planck.jobcontroller]
[W] void __cdecl LibrarianController::updateCurrentCollectionController(void) Can not fetch current collection           [2024-01-17T16:42:51.156Z] [air.planck.database     ]
[W]  controller.                                                                                                         [2024-01-17T16:42:51.156Z] [air.planck.database     ]
[W] std::runtime_error executing "Updating track list" Unexpected error:29                                               [2024-01-17T16:42:51.156Z] [air.planck.jobcontroller]
[W] 0x01290a71 in Engine DJ            0x01290cb1 in Engine DJ            0x0043ef00 in Engine DJ                        [2024-01-17T16:42:51.156Z] [air.planck.jobcontroller]
[W] 0x00cdda91 in Engine DJ            0x004561f9 in Engine DJ            0x00cf938e in Engine DJ                        [2024-01-17T16:42:51.156Z] [air.planck.jobcontroller]
[W] 0x00cf89ea in Engine DJ            0x0043ba80 in Engine DJ            0x0043d733 in Engine DJ                        [2024-01-17T16:42:51.156Z] [air.planck.jobcontroller]
[W] 0x00459281 in Engine DJ            0x0086bb8c in Engine DJ            0x00009638 in KF5ThreadWeaver                  [2024-01-17T16:42:51.156Z] [air.planck.jobcontroller]
[W] 0x0000884c in KF5ThreadWeaver      0x0086b43d in Engine DJ            0x00007f44 in KF5ThreadWeaver                  [2024-01-17T16:42:51.156Z] [air.planck.jobcontroller]
[W] 0x000268c8 in Qt5Core              0x0001257d in KERNEL32             0x0005aa58 in ntdll                            [2024-01-17T16:42:51.156Z] [air.planck.jobcontroller]
[W] [ 0x2371334af08 ] Job Failed "Updating track list" ""                                                                [2024-01-17T16:42:51.159Z] [air.planck.jobcontroller]
[W] [ 0x2371334af08 ] Job Failed "Updating track list" ""                                                                [2024-01-17T16:42:51.159Z] [air.planck.jobcontroller]
[W] QObject::connect(StemProcessNotifier, StemPlaybackController): invalid nullptr parameter                             [2024-01-17T16:42:51.170Z] [                        ]
[W] QObject::connect(StemProcessNotifier, StemPlaybackController): invalid nullptr parameter (repeated 13 times)         [2024-01-17T16:42:52.206Z] [                        ]
[W] MigrationFinished uuid for path  "76e4d653f7c2b731"   "b86694df-xxxx-4f35-8eca-bda012e89c98"                         [2024-01-17T16:42:52.206Z] [air.planck.database     ]

This is just loading Engine DJ Desktop.

Unfortunately I no longer use synchronization, I drag my music from the laptop straight to the internal drive of my Prime 4 (through the desktop dj engine of course), I’m tired of having problems with this synchronization, I deeply hope that this system is more efficient and easy to use.


Yeah, I have so many people telling me that this is how they’ve worked around this issue. Unfortunately for me, I don’t only mix one genre of music, and I get new tracks so often that I really need separation at the genre level, so I need the tracks to be part of a database so that I can apply such filters.

I am unwilling to spend hours doing a task that a computer should be capable of doing within seconds.

My suggestion to all that have slow syncing is to try a fresh main database.


Don’t just wipe the export drive but rename/zip the pc database.

Reimport your tracks to engine dj pc/desktop and try a new export/sync to the formatted export drive

Have you tried just dragging the playlists onto the drive within engine rather than using sync manager? I sometimes use this method if sync manager is taking too long.