Virtual DJ and LAUNCHPAD clashing input

[Gwedo]

So we had a party last week and we had a DJ booth with a laptop running virtualDJ and QLC+.

I had set my universe 1 to the launchpad to simply select scenes and chasers with the press of a button.

On universe 4 I had virtualdj input using os2l. This gave me a beat input, which I connected to a tap function so my scenes would run and change at the BPM of a song playing.

This worked for about 2 hours, but after some time QLC decided it was time for the launchpad to go and it disconnected it, and I got an error when I tried to change it back as input.

I would had to restart qlc and the music (which I didn't do to save the party) but how do I fix or prevent this, or is this a common problem when using multiple midi divices?

[mcallegari]

Yeah...QLC+ disconnects USB devices...lol

[edogawa]

Same or similar has happened to me just recently, so I tend to take that report more serious. In my case a NanoKontrol2 was connected to the PC's front panel USB port, patched as input to universe 4 and controlling just a cuelist's next/previous buttons and cross fader. It worked for several hours before and up to 20 minutes into the show.

At that point in the piece I have to leave the booth to operate another QLC laptop in a second performance hall, and my sound colleague runs six scene changes during the next hour of this theater show. When I came back he told me the NanoKontrol had stopped working, but he had found his ways around using the mouse.

Looking at the I/O tab I saw that universe 4 was now connected to other MIDI ports for Input and Feedback (my Delta 1010LT ones to be precise). Trying to reconnect to the correct ones gave an error dialog, but after un- and replugging the USB cable I was able to change back to the NK2.

That same thing happened a second time a few days later, a bit earlier into the show, so I was able to reconnect before leaving.

Even if QlC+ doesn't deliberately disconnect the device, it seems that if for whatever reason a MIDI controller can get disconnected, and leave QLC+ in a state where it cannot communicate with it anymore despite hotplugging enabled. I'm not talking about Voodoo or black magic, but things like these can and do occur sometimes in live situations. I don't blame QLC+ for that, nor careless setup from my side. It's an old place with old electrical installations and lots of video/sound/light cables and wireless signals everywhere.

I don't know what happened to the OP, but I can relate to his story. He might just have worded his experience unluckily.

[GGGss]

In the very advanced windows settings -> disable power saving on all USB ports.
I too lost connection to the Launchpad... this was during a lunch break before showtime. A change of these settings and a restart did solve it.

[Gwedo]

In the very advanced windows settings -> disable power saving on all USB ports.
I too lost connection to the Launchpad... this was during a lunch break before showtime. A change of these settings and a restart did solve it.

Thanks, I will try this!

[Gwedo]

Same or similar has happened to me just recently, so I tend to take that report more serious. In my case a NanoKontrol2 was connected to the PC's front panel USB port, patched as input to universe 4 and controlling just a cuelist's next/previous buttons and cross fader. It worked for several hours before and up to 20 minutes into the show.

At that point in the piece I have to leave the booth to operate another QLC laptop in a second performance hall, and my sound colleague runs six scene changes during the next hour of this theater show. When I came back he told me the NanoKontrol had stopped working, but he had found his ways around using the mouse.

Looking at the I/O tab I saw that universe 4 was now connected to other MIDI ports for Input and Feedback (my Delta 1010LT ones to be precise). Trying to reconnect to the correct ones gave an error dialog, but after un- and replugging the USB cable I was able to change back to the NK2.

That same thing happened a second time a few days later, a bit earlier into the show, so I was able to reconnect before leaving.

Even if QlC+ doesn't deliberately disconnect the device, it seems that if for whatever reason a MIDI controller can get disconnected, and leave QLC+ in a state where it cannot communicate with it anymore despite hotplugging enabled. I'm not talking about Voodoo or black magic, but things like these can and do occur sometimes in live situations. I don't blame QLC+ for that, nor careless setup from my side. It's an old place with old electrical installations and lots of video/sound/light cables and wireless signals everywhere.

I don't know what happened to the OP, but I can relate to his story. He might just have worded his experience unluckily.

Yeah it happend last week so I can't really remember how it exactly went but when I was testing at my home desktop, everything worked. but when at the party my laptop just didnt coop

[mcallegari]

I was making fun of the fact that some users think QLC+ disconnects USB devices. No. It's Windows that decides what to do with your hardware.
It's actually quite difficult to handle hotplugging from within QLC+.
Also, there are lots of posts discussing about the usage of a USB HUB rather than native USB ports, especially on laptops where, as Fredje indicated, there are a few energy saving settings to keep in mind.

[Gwedo]

I was making fun of the fact that some users think QLC+ disconnects USB devices. No. It's Windows that decides what to do with your hardware.
It's actually quite difficult to handle hotplugging from within QLC+.
Also, there are lots of posts discussing about the usage of a USB HUB rather than native USB ports, especially on laptops where, as Fredje indicated, there are a few energy saving settings to keep in mind.

I will consider using a hub from now on, I could see how this would improve things since your pc only outputs to one USB port. I also dissabled the energy saving mode on the USB-Root.

[Gwedo]

I tought it was because of using multiple MIDI controllers that QLC somehow messed them up. But I see how the USB, and hotplugging could indeed be the source of this issue.

[GGGss]

I was making fun of the fact that some users think QLC+ disconnects USB devices. No. It's Windows that decides what to do with your hardware.
It's actually quite difficult to handle hotplugging from within QLC+.
Also, there are lots of posts discussing about the usage of a USB HUB rather than native USB ports, especially on laptops where, as Fredje indicated, there are a few energy saving settings to keep in mind.

I will consider using a hub from now on, I could see how this would improve things since your pc only outputs to one USB port. I also dissabled the energy saving mode on the USB-Root.

I will keep my DMX interface connected to the native USB ports and not the hub. (Mostly because I noticed that DMX interfaces need dedicated power... just saying for stability reasons

[djnikkofb]

I actually use a HUB with my Novation Launchpad & Virtual DJ.
Pro Tips
Disable Launchpad within Virtual DJ (So it will not recognize when plugged in)
Use a Thunderbolt 3 or 4 (I use 4 since I have the capability). Don't buy a cheap one, you will need to spend over $200 for a good POWERED Hub. ONLY Use a Powered Hub.
Everything will work as intended.. Trust me.

[kenact]

Here's an article about disabling USB Selective Suspend

https://www.technewstoday.com/usb-selec ... d-setting/