CDJ-2000nxs2 metadata issue

[trickofdjequip]

Hello. Today we trying 1.9.0 version in full show. 2x2000nxs2 wired into switch and connected with win11 laptop at FOH through cat6 100m. Almost all the time metadata not going. ~15 minutes later metadata is loaded on 1 track.

full show.pcapng.zip

This is wire shark file writing full show.

Also our Dj have issues with 2000nxs2. Player did no react on bottons. May be this help you.

[fiverecords]

Thank you for the capture — a full show Wireshark trace is incredibly valuable. I analyzed all 37 minutes and found three bugs in STC that together explain everything you experienced.

Bug 1 — Double notify causing doubled CDJ traffic
STC sends its bridge status (0x55) from two different sockets simultaneously. The CDJ registers each source port as a separate subscriber and sends status updates to both — your CDJs were sending 10-13 status packets/sec instead of the normal 5. When STC's internal socket changed at ~minute 10, the old subscriber was never cleaned up, so ghost subscribers accumulated. This extra load contributed to both CDJs freezing for 22 seconds at the 15-minute mark.

Bug 2 — Port 65535 (invalid database port)
When STC queries a CDJ-2000NXS2 for its database server port, the CDJ sometimes returns 65535 (0xFFFF = "no service available"). STC's validation has an off-by-one error that accepts 65535 as valid, then tries to TCP connect to port 65535 — which fails. In the capture I can see 5 failed connection attempts to CDJ1:65535 at the 15-minute mark.

Bug 3 — Zombie NFS connection blocking metadata
This is probably the main reason metadata didn't work. STC opened an NFS connection to CDJ1 at startup that went idle immediately. For 10 minutes (0:16 to 9:36), both sides exchanged TCP keepalive probes every 10 seconds on this dead connection — 120 retransmission pairs. The CDJ-2000NXS2 has limited NFS connection slots, and this zombie connection was occupying one, blocking actual metadata requests from going through. CDJ2 also had NFS retransmissions with exponential backoff (2s, 4s, 8s, 16s, 32s) at minute 13-14 where STC wasn't acknowledging NFS data.

All three fixes are straightforward and will be in the next build.

One question: in the capture I also see StageLinQ discovery broadcasts (UDP port 51337) from STC at 1 packet/second throughout the session. Did you have StageLinQ configured as input on any engine? If not, that's unnecessary broadcast traffic on the CDJ network — we've also fixed this so StageLinQ now stops automatically when no engine uses it.

[fiverecords]

Please check the new version

[trickofdjequip]

Did you have StageLinQ configured as input on any engine?

no, I don't use it.

Please check the new version

I'm check new version 16.04 on CDJ-3000 and 18.04 on nxs2. ofc i'm recording wireshark captures.

Also I have one improvement request: my DJ have over 3000 tracks in collection (sic). For events he make playlists. In .xml file this look like order of track ID:

<PLAYLISTS>
    <NODE Type="0" Name="ROOT" Count="2">
      <NODE Name="TEST" Type="1" KeyType="0" Entries="5">
        <TRACK Key="57"/>
        <TRACK Key="59"/>
        <TRACK Key="61"/>
        <TRACK Key="63"/>
        <TRACK Key="65"/>
      </NODE>
      <NODE Name="2003 - Absolution" Type="1" KeyType="0" Entries="0"/>
    </NODE>
  </PLAYLISTS>

Can you integrate playlist import into track map? ofc with track order.

test_playlist.xml

[fiverecords]

Good idea, this is implemented for the next release.

When you import a rekordbox XML file that contains playlists, STC will now show a dialog where you can either pick a specific playlist or import the entire collection. If you pick a playlist, the tracks are imported into the Track Map in playlist order — so your DJ can prepare the setlist in rekordbox, export as XML, and you get the tracks in the right order for pre-programming timecode offsets, triggers, and cue points.

Thanks for the XML sample, it was very helpful for testing.

[fiverecords]

It wasn’t difficult with the base I already had, so there’s a new release with the playlist import feature.

[trickofdjequip]

Laser speed release! I trying this with my dj's collection.

So, At the upcoming show, even if there are no problems, I will still be writing Wireshark captures. May be you need another data?

[fiverecords]

Thanks! Let us know how the playlist import works with the collection.

And yes, a capture from a clean show is very valuable — it lets us verify the v1.9.1 fixes are working correctly under real conditions. If you can:

• Wireshark on the STC machine, capture on the CDJ network interface
• Let it run for the full show (or at least 30 minutes)
• Save as .pcapng, no filters needed

Thanks again for testing!

[trickofdjequip]

Hello. today we make show with CDJ-3000. All work correctly. Win10, STC->vbAudio->resolume.

show v2.pcapng.zip - wireshark capture from show.

I found mistake in import from .xml: when tracklist name include dot tracks don't import.

We work in 25fps. When we restart STC fps changes to 30. Restore from backup change fps too.

New features request:

1. Connect mixer channel fader with engine output. DJ can load and play tracks with 2 player at same time. Today we just turn off engine output while saw it. But we can connect mixer channel fader to engine output. for example 0-20 turn off, 21-127 turn on.

2. Track map - sort by artist name, title, offset. Like in finder or explorer in operation systems.

Today everything worked just the way I wanted. Endless gratitude!

[fiverecords]

Glad the show went well! I checked the capture and everything looks clean on the Pro DJ Link layer.

The issues you reported have been identified and will be fixed in the next version:

The playlist import problem wasn’t actually caused by the dot — it was due to the folder path parser splitting on every space and slash instead of the " / " separator. This caused failures when folder names contained spaces.
The 25 → 30 fps reset was also a bug: the input start function was overwriting the configured frame rate on every startup.

The two feature requests (fader threshold for engine output, sortable Track Map columns) are noted and planned for a future update, as they require some UI work.

Thanks for the detailed capture and the feedback!

[fiverecords]

Please check the new version

[trickofdjequip]

Win10, STC->vbAudio->resolume. With 2000nxs2 work incorrectly. Start good, but after half hour players start stuttering.

Unfortunately, I didn't have time to record the results right away. The file below will contain the results after the stutters.

2000.pcapng.zip

[fiverecords]

Thanks for the capture. The 130 s it contains are from after the problem started, so at the network level everything looks normal (~5–7 status pps per CDJ, no floods). That’s not enough to diagnose the cause — I need to see the transition from “all good” to “stuttering starts”.
That said, after reviewing the dbserver protocol documentation and other reference implementations that have been field-tested on CDJ-2000NXS2 for years, I found one concrete difference I’ve fixed in the next release.
The client should send a dbserver protocol teardown message before closing the TCP socket. STC was closing the socket unilaterally. The documented approach is to send a small message (magic TxID 0xfffffffe, type 0x0100, 32 bytes) that causes the CDJ to close from its side, which lets the firmware properly release the dbserver session state. Unilateral closes can leave half-released sessions accumulating in the CDJ’s firmware over a long set.
I’m not selling this as the definitive fix for the stuttering — I don’t have data to prove it — but it is a real difference from the established way of talking to NXS2 without these issues. Try 1.9.4 in a long set.
If the stuttering comes back, I need a capture covering from the start through after it begins. With that I can diagnose without speculating.
A few questions that would help in parallel:
• Does it happen on both CDJs or just one?
• During track loads, or during steady playback?
• If you disable the ProDJLink input in STC, does the stuttering stop?
• Does it reproduce with just one CDJ on the network?
• What firmware are the CDJ-2000NXS2 on? There’s a historical bug (fixed in firmware 1.13) of “after several hours the browse screen becomes slow or stops”, so if they’re on an old version it’s worth ruling out.​​​​​​​​​​​​​​​​

[trickofdjequip]

Okey. Today we swap nxs2 to 3000x. This setup work correctly. Next week I’m testing nxs2

[fiverecords]

Please check the new version

[trickofdjequip]

Hello. Today I'm testing nxs2 setup. Win10, STC 1.9.4. flash drive in player3.

Archive.zip - wireshark captures.

Player1 glitched when I pressed 'browse' botton.
After that I'm reconnect rg45 from player1. But 30 seconds later it glitch second time.

While flash drive was in player1, I have mirrored captures.

player1 with usb.pcapng.zip
This capture have info about 2 reboot of player3