Special Instructions for Windows Users Installing Multiple USB LRT Boards

This tutorial is for PC users who are having trouble with Hauptwerk losing track of (and seemingly renaming) your MIDIWorks Lighted USB Rocker tabs. If you're just having trouble getting them to light up for the first time, it's a configuration problem and you should refer to the tutorial on installing them initially. You missed something. Start there first.


Understanding the problem:

Each LRT has a unique device name which is determined by the dip switch settings on the board. The name shows up as "CLASSIC lighted rocker xx-xxx" where the exes are the channel and starting tab-number for the board. 

The problem is an issue with the relationship between Window's device manager and the Audio/MIDI driver. The Windows device manager correctly names each device (Start Button > Devices and printers). However, those unique names are not passed on to the Audio/MIDI driver. Instead it takes the name first device scanned and uses that name for all similar devices attached to the computer. It adds a letter after each device of the same type in order to identify it.

So, if there are CLASSIC lighted rocker 01-000 and CLASSIC lighted rocker 03-016 attached, Hauptwerk will show up choosing a random board-name with A, B or C etc at the end. So you'll see


CLASSIC lighted rocker 01-000

CLASSIC lighted rocker 01-000A


in the MIDI ports window. In itself, that's not horrible because you can still configure it as long as the names remain stable.


Making things stable:


Start with the computer off


1) Get all the MIDI LRTs ready to plug in to the computer. Make sure all are on different channels and/or different starting numbers. They can have the same starting number if they are on different channels. I think you've done this already.

2) Plug all of them into your computer directly or via a hub before you power up the computer.

3) Power up the computer.

4) Open up Hauptwerk and enable all the MIDI ins and outs for those devices (like you've been doing)

5) While the computer is on, do not plug in or unplug any USB device.

6) Configure two onscreen draw knobs (like we've been doing) with THIS IMPORTANT EXCEPTION. Set the in and out ports to "any enabled port" for each drawknob. 

7) Test that they work as expected.

8) Now reboot and restart Hauptwerk.


You should not get the "missing devices" message. However, if you do, continue anyway. You may have to enable all the MIDI ports again under new names. However, your configuration won't be wiped out and the draw knobs should still light up the tabs.

When the computer starts up, it should be scanning for USB devices in the same order every time. So, as long as nothing new is plugged in or unplugged, it should find them all. I'm not sure if it works the same with hubs but this is how it works on my machine.  

As long as you have the MIDI input port and MIDI output port set as "any enabled port", you should be fine even if the devices are renamed. The reason you'll be ok is that each device has a unique channel and tab-number combination.


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