diff --git a/Setup-Computer-Debian-12.md b/Setup-Computer-Debian-12.md
index 752279d..fc65f27 100644
--- a/Setup-Computer-Debian-12.md
+++ b/Setup-Computer-Debian-12.md
@@ -147,13 +147,16 @@ sudo cp ~/work/stxm/SystemInstall/comedi.conf /etc/modprobe.d
 
 
 - compile Pixelator
+
+Warning: Running compile jobs in parallel (i.e. using the `make -j#` option with #>1) can cause compile errors, especially for PixelatorGUI.
+
 ```
 cd ~/work/stxm
 autoreconf -i
 mkdir build
 cd build
 ../configure
-make # do not use -j, at least not for the GUI
+make
 cd PixelatorController/config/
 make    # for the config files
 cd ../../PixelatorGUI/config/