AutoDJ + USB MIDI/HID controller + moving crossfader to "Deck A" = "fails to trigger Deck A auto play"

[nPrevail]

Bug Description

System specs:
Fedora 37 /GNOME 43
12GB DDR4
Ryzen 2400GE

Problem:
When you're using a DJ controller (I was using the Traktor S4 MK2), and when you have AutoDJ is enabled, when you try moving the crossfader (on the midi controller) to "Deck A", the crossfader fails to trigger the auto play.

Now, I can trigger the auto play on Deck A if I push the keyboard key "G" multiple times until the crossfader reaches Deck A. I can also trigger Deck A by using my cursor to move the crossfader to Deck A.

The video below demonstrates using the MIDI controller's crossfader, and it shows that I'm able to use the MIDI controller's crossfader to trigger the auto play in Deck B. But unfortunately, Deck A does not auto play any tracks when you move the DJ Controller's crossfader towards it.

Recommendation:
When AutoDJ is enabled, and when you're using a DJ MIDI controller, the crossfader from the MIDI controller should reflect the crossfader on Mixxx. The crossfader should be able to auto play tracks from either decks.

Video:
Screencast from 2023-05-08 23-14-54 (720p).webm

Version

2.3.4

OS

Fedora 37 GNOME 43

[daschuer]

It looks like as if the crossfader of your Traktor S4 MK2 is not able to reach the fully left position. This is not alone an Auto DJ issue. This is also an issue that the engine always need to process the Crossfader gain != 1.

Please confirm this assumption by starting Mixxx with mixxx --developer, open the Developer menu and then "Developer Tools". There scroll to [Master], crossfader and watch the value column. The expected values are -1 ... 1.
If you are not able to reach them we need to adjust the mapping scaling of the values.

[ronso0]

There scroll to [Master], crossfader and watch the value column.

Or use the searchbox in that window ;) [Master],crossfader
Btw for some (all) controls the Dev Tools window has to be focused to see the value updates instantly.

[JoergAtGithub]

The NI Traktor crossfaders usually needs to be calibrated. See the procedure for the S4 Mk2 here: https://support.native-instruments.com/hc/en-us/articles/210274845-Fader-and-Knob-Calibration-of-TRAKTOR-KONTROL-Devices#Recalibrating%20your%20TRAKTOR%20KONTROL%20MK1%20/%20MK2%20devices%20including%20KONTROL%20Z1%20/%20Z2

The calibration values are usually stored in HID FeatureReports, as reengineered here for the S2 Mk1: #11237

[nPrevail]

You're right! I completely forgot about the S4 controller calibration. So for a user like myself, who's using Fedora Linux and mixxx, can anything be done to recalibrate the controller?

…

On Fri, May 12, 2023, 11:49 JoergAtGithub ***@***.***> wrote: The NI Traktor crossfaders usually needs to be calibrated. See the procedure for the S4 Mk2 here: https://support.native-instruments.com/hc/en-us/articles/210274845-Fader-and-Knob-Calibration-of-TRAKTOR-KONTROL-Devices#Recalibrating%20your%20TRAKTOR%20KONTROL%20MK1%20/%20MK2%20devices%20including%20KONTROL%20Z1%20/%20Z2 The calibration values are usually stored in HID FeatureReports, as reengineered here for the S2 Mk1: #11237 <#11237> — Reply to this email directly, view it on GitHub <#11546 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ANYETW3FRD6HCMAWLQX57Y3XF2A5DANCNFSM6AAAAAAX3LIXAM> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[JoergAtGithub]

Plug it to a Windows or Mac sytem, run the fader calibration. The calibration values are stored in the device and will be available under any OS then I don't know if they are automatically taken into account, or if you need to modify the mapping.

[nPrevail]

Hm, not sure if that works... I've calibrated the S4 Mk2 in Traktor Pro 3 and Windows in the past. These values don't seem to transfer to Linux just because they're calibrated in Windows, but I'll give it a shot again.

…

On Sun, May 14, 2023, 06:18 JoergAtGithub ***@***.***> wrote: Plug it to a Windows or Mac sytem, run the fader calibration. The calibration values are stored in the device and will be available under any OS then I don't know if they are automatically taken into account, or if you need to modify the mapping. — Reply to this email directly, view it on GitHub <#11546 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ANYETW6CCTK2VSEFPYLRZKTXGDLRXANCNFSM6AAAAAAX3LIXAM> . You are receiving this because you authored the thread.Message ID: ***@***.***>