diff --git a/mbricks/CMakeLists.txt b/mbricks/CMakeLists.txt
index 45db234..6148010 100644
--- a/mbricks/CMakeLists.txt
+++ b/mbricks/CMakeLists.txt
@@ -5,7 +5,7 @@ if (NOT LIBPROJECT)
 endif ()
 include_directories(${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR} ${PIP_INCLUDES})
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O2 -Wall")
-#set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g3")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g3")
 set(CMAKE_C_FLAGS "${CMAKE_CXX_FLAGS}")
 
 file(GLOB HDRS "*.h")
diff --git a/mbricks/brick_math.cpp b/mbricks/brick_math.cpp
index 6085870..1e5a5db 100644
--- a/mbricks/brick_math.cpp
+++ b/mbricks/brick_math.cpp
@@ -185,10 +185,13 @@ bool BrickMathFFT::tick_body(double time) {
 		buffer.resize(t, 0.);
 		t = 0;
 	}
-	outputs[0] = o[t].real();
+	outputs[0] = (t >= 0 && t < o.size_s()) ? o[t].real() : 0.;
 	if (t >= v.size()) {
 		t = 0;
-		//fft(o.data(), log2((double)v.size()), parameters[1].toInt() > 0.);
+		if (parameters[1].toInt() > 0.)
+			o = *fft.calcFFTinverse(v);
+		else
+			o = *fft.calcFFT(v);
 		for (uint i = 0; i < buffer.size(); ++i)
 			buffer[i] = abs(o[i]);
 	} else {
diff --git a/qad_graphic/graphic.h b/qad_graphic/graphic.h
index 9757295..6f01aac 100644
--- a/qad_graphic/graphic.h
+++ b/qad_graphic/graphic.h
@@ -320,7 +320,7 @@ protected:
 	void setCurrentAction(GraphicAction action);
 	void findGraphicsRect(double start_x = 0., double end_x = 0., double start_y = 0., double end_y = 0.);
 	void tick(int index, bool slide = true, bool update = true);
-	void repaintCanvas(bool force = false) {if (tm.elapsed() < min_repaint_int && !force) return; tm.restart(); canvas->update();}
+	void repaintCanvas(bool force = false) {if (tm.elapsed() < min_repaint_int && !force) return; tm.restart(); canvas->repaint();}
 	void drawGraphics();
 	void drawGrid();
 	void drawGuides();