Cubase Pro crashes when using MIDI controller FQC

Am hoping some programming gurus are on this site, who may be able to explain
why Cubase pro 12 keeps crashing when I use a teensy4.1 based rotary encoder midi control surface
when I specifically use it to control focus VST Track quick controls.

I created the control surface which has 8 rotary encoders on it (nothing else),
where each rotary encoder sends Control Change messages (control, value, channel);
I first programmed the teensy so that each rotary encoder sends the data using the same controller on a different channel
The second time around, I programmed each rotary encoder to send data on a different undefined CC number (46-53), on the same channel (channel 1).

Again, when using to control regular features of a channel such as vol, pan, eq, or track QC.
it was fine, but when using to control FX plug in (UAD-2) using focus qc
it works for a short time and then dumps out

control surface appears to map ok in the new mapping assistant

Any idea what could the matter be?
Would be grateful for any advice on the subject.


Attach the crash/DMP file(s), please.

Hello Martin
Thanks for your reply. The file is as follows. I presently do not have any app to open this file.
I also am not experienced in such types of debugging analysis.
Any help would be appreciated. Thanks

Cubase 64bit 2022.7.9 (846.7 KB)


Ulster to the latest Cubase 12.0.30, please.

Hello. OK. Will do.
Just been testing out my control surface, and it does work with focus quick controls
at least at first. Although after about 2 mins 20 sec, the midi controller stops working,
Works again on reboot, so I wonder if it is something to do with the midi controller itself.

The last time the midi controller stopped working
cubase didn’t produce a crash file, perhaps didn’t crash the program
just the controller. ;-(

Hello. I updated as suggested.
I did some further testing today
and think i have figured out the cause to the controller crash
in this case, i think it wasn’t software based
but hardware
i tried using the focus QC with a plug in, for several minutes
and the controller didn’t crash when using 1, 3-8 rotary encoders
the controller crashed if however i used the number 2 rotary encoder
on closer inspection of the wiring
the encoder used for no 2 wiring was a bit dodgy
one of the wires wasn’t soldered very well, and likely touched the ground
if the encoder was wiggled enough - so causing a short and causing the device to crash

so. good news really as its simple enough to re-solder the encoder or replace with a new one

that’s a big relief, as this i can do quiet simply, where as the whole debugging
and coding i am very inexperienced in

but you learn by your mistakes
so all good
thanks for the offer to help Martin
much appreciated

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