Results from live testing STC

[Joren2087]

Hi all

Didn't know where to put this so I guess it goes here.

Yesterday I ran STC v1.9.5 for a live busking & timecode show for almost 8h of dj'ing on a 4xcdj3000 + djm A9 setup. Here are my results and finding about the stability of STC in a live production environment using it both as a timecode source as well as show control using the PDL view in the pro dj link module.

First of all: it worked great and I'll definitely use it again in the future!

We only had to restart stc once because the detailed waveforms didn't show up anymore in the PDL view (after it was open & running for 10h+). General track metadata such as title, bpm etc did update as well as full track waveform, just the detailed representation didn't show up anymore at some point, but restarting stc fixed it. Notably it stopped when a new DJ came up, I first thought the DJ's audio files didn't have a record in rekordbox but even after that DJ it still didn't came back. Maybe an issue with new USB source in cdjs and/or switching back from tracks with no metadata?

Also the djm didn't show up in the PDL view, but that should have been fixed in v1.9.8 (wasn't able to test).

Another thing I noticed was that it would be nice to have an 'any' of option in the pro dj link source selection for timecode input. While 'on air' might have worked, I couldn't get it working due to the djm not loading in stc. Then again I wouldn't even care about the on air status as the timecode input (in my case) can be set the moment one of the tc'd tracks is loaded on any of the cdj's.

Another mildly annoying thing was that our timecode audio track wasn't imported in any rekordbox database (just copy+pasted on de USB root dir). This caused STC to not recognize the new track being loaded and just display the old track (don't know anymore whether it was only track metadata and/or waveform that didn't load). (For future readers: you can likely avoid this by using the TC generator with audio playback introduced in v1.9.7).

Also for any uninvolved readers: while 1.9.7 was released at the date of the show (and had some nice new features like proper TCNet /Chamsys MagicQ integration and audio playback I the generator module) it was unstable to due a crash introduced in v1.9.6 but should be fixed in v1.9.8 (see release notes).

That's pretty much all I had to say about STC. I absolutely will use it again and can recommend it to others. This is definitely a considerable showkontrol alternative (especially when budget doesn't allow / MacBooks aren't an option).

Thanks for the great work and keep it up!

[fiverecords]

Hi @Joren2087, thanks for the detailed writeup, this is exactly the kind of field test that helps most. Really glad it held up over 8h.

A few replies:

Detailed waveforms stopped showing up after 10h+ in 1.9.5: noted. The fact that title / BPM / full-track waveform kept updating but only the detail view got stuck suggests the dbserver detail-waveform fetch path entered a state it couldn't recover from -- something like a request sent but never replied to, or a cache slot stuck in "already requested" without retry. 1.9.6 reworked some of that path (idle timeout, transaction-ID validation, immediate close on read failure) which would help here in principle, although none of it was written with this specific symptom in mind. If it recurs on 1.9.8 over a similarly long session, a Wireshark capture covering the moment it stops would be very useful -- second best, just note approximate uptime and track-load count when it happened.

'Any of' input source for ProDJLink: makes sense, added to the backlog for the next release. The behaviour I'd implement: any player with a track carrying a recognised TC offset becomes the active source, with a configurable priority order if multiple qualify simultaneously. Does that match what you had in mind?

Track not in rekordbox not recognised: correct -- the recognition key is built from the metadata the dbserver returns, so tracks copy-pasted to USB root have no entry to match against. The 1.9.7 generator-with-audio-playback feature sidesteps this for the timecode track itself.

DJM-A9 not appearing: fixed in 1.9.8.

Really appreciate the writeup. Thanks

[Joren2087]

Yes - The 'any of" input is exaclty described as I would do it. With some kind of priority ordering would be nice to prevent accidents.

When a recognition key is not found, would it be possible to at least show that on the PDL view (and all subsequent features in the pipeline)? Maybe with the bare minimal info you can find about it (idk if track path/name is available)? Otherwise, just show something like "Couldn't find recognition key in dbserver. Is the track in the rekordbox database?".
This would be more descriptive than just showing the last track with a valid recognition key in dbserver (which isn't valid for the current playing track and causes confusion).

[fiverecords]

Hi @Joren2087,

Good feedback on both -- here's where each one lands:

Following whichever CDJ is currently active: instead of a generic "any of" picker, the cleanest approach is to follow the CDJ that has the MASTER flag set on the link -- the DJ already controls that explicitly from the deck (the MASTER button on the CDJ), so it doubles as the priority ordering you mentioned. Whatever CDJ the DJ taps MASTER on becomes the timecode source, and STC stays on it as long as it holds master, switching when another deck takes it. That should cover the show-control use case you described without adding a separate priority list to configure.

Track-without-rekordbox-entry showing the previous track's info in the PDL view: I want to fix this but the right fix depends on what the CDJ actually puts in its status packets when the loaded track has no rekordbox entry -- there are several possibilities (track ID stays at 0, track ID gets reused from the previous track, track ID gets a synthetic value) and the right fix is different in each case. If you ever happen to be in front of the hardware again with no pressure and can grab a Wireshark capture of the swap from a rekordbox track to a non-rekordbox one, that would let me ship the fix cleanly -- but no rush at all, I know you said hardware access is limited.

Thanks again for the detailed reports.