The Lighting Controller

Hi,

I'm recently experiencing USB disconnects during our shows, with the last one being Saturday with 3 dropouts during a 2 hour set.
First two times I restarted QuickDMX and everything went on directly. 3rd time I disconnected and connected the USB cable from the D512 which also enabled the lighting again.

The D512 is connected directly to a Macbook (without any USB hub) and the DMX line is going to a Showtec 1-8 splitter/booster. The Macbook is always net powered (behind a power conditioner).

I've read through several posts on this forum and read about USB hubs and ground loops. However with no USB hub used and the usage of the showtec these two should not be the problem in my case, I guess.
I would think of trying a different USB cable.

Do you maybe have other tips or insights on this?

No need to restart our software after DMX interface unplug / replug. Our software is supposed to auto re-take control of our DMX interface after a few seconds.

We see 3 possible causes for this problem:
- bad USB cable
- electrical problem on DMX line ("ground loop")
- power lack (solution is a powered USB hub)

Good to know unplug/plugin the unit will have immediate effect to the software, thanks.

So in our case it would be a possibly bad USB cable. Ground loop is impossible due to the Showtec splitter (which is isolated between in- and outputs) and we don't use a USB hub as we connect the box directly to one of the USB ports of the Macbook.
Will try a new cable which will hopefully solve the dropouts..

Oof, sounds like a nightmare scenario.

Don't know how it is for Mac, but for PC you could try:
- other USB port
- in Windows, you can select that the usb port doenst go in sleep mode, maybe something simular possible for Mac?


Good luck!

We tried a new USB cable and had a test run for about 2,5 hours and so far no disconnects.
Going to do some test runs the upcoming weeks during rehearsals so hopefully the new cable will do the trick

Good news !
Thank you for the feedback.