QLC+ v4 Crashing with Eurolite USB DMX 512 Adapter

[ProfSam]

Hey everyone,

I’ve encountered a somewhat interesting issue. I recently bought a Eurolite USB DMX 512 (not the pro version) from Thomann, and it arrived today. I installed the latest FTDI D2xx drivers (not the VCP version) and tried to launch the latest version of QLC+ v4, but it wouldn’t open. However, when I disconnect the USB adapter, QLC+ starts up normally. If I plug the adapter back in while it’s running and attempt to refresh the USB DMX devices, QLC+ crashes again.

It’s definitely not a hardware issue since the adapter works fine with PC_Dimmer, and it also shows up in QLC+ v5. I would love to use v5, but I need a stable version, as this is for our school.

I’ve already reinstalled QLC+ and tested it on two different Windows laptops, but that didn’t solve the issue. I would really appreciate any help!

Update: I tested it with Ubuntu 22.04 and it works just fine, but I still need help for Windows 11.

Best regards,
Sam <3

[mcallegari]

Hi, just double checking: can you try with version 4.12.7 and report if it works?
Thanks

[ProfSam]

Hi, just double checking: can you try with version 4.12.7 and report if it works?
Thanks

Thanks for your quick response! I tested it with 4.12.7, and it works just fine. Will there be a fix in future versions, or should I just stick with 4.12.7?

[mcallegari]

It has to work also with the latest versions.
I'm gonna check what's wrong with it.

[ProfSam]

Nice, thank you very much for your efforts! Let me know whether I can provide any further details.

[mcallegari]

I just tested the adapter with Windows 11. No problems at all.
You might have DLL conflicts described in other threads.
See https://www.qlcplus.org/forum/viewtopic.php?t=17163
On Windows, you don't have to install any driver at all manually.
On device plugging, Windows will install the proper drivers for you.

In fact I never plugged this Eurolite adapter and I didn't even have QLC+ installed.
Everything worked out of the box without installing any driver.

[ProfSam]

Hey, thanks for the testing. I uninstalled all FTDI-related drivers from my laptop (Windows 10) and tried again, but it still didn't work. Then, I used my desktop PC (Windows 11, updated the night before), which had never been used with the Eurolite adapter or any other similar device, and I didn't install any drivers there either, but it still didn't work.

After reading through the thread you mentioned, I deleted the ftd2xx.dll from QLC+ v4, and this time it did work. However, as mentioned in the thread, the USB plugin did not show up. I also deleted any ftd2xx.* files I could find on my system, but it still didn't solve the issue. I tried disabling the serial device in Windows Device Manager and/or uninstalling the USB adapter along with its drivers.

After all of the above, I decided to order a new cheap adapter from Amazon (https://amzn.eu/d/3lAgV91), which seems to be the one from the mentioned thread. It works right out of the box on all of my devices (Windows 10 at school, Windows 10 on my laptop at home, Windows 11 on my desktop) on QLC+ v4 4.12.7 and 4.13.1.

Did I miss something from the mentioned thread?

If you have any other suggestions, I'm happy to try them.

Thank you for your time!