diff --git a/client/Mac/MRDPView.h b/client/Mac/MRDPView.h
index 51eb8f549..ea531c8b1 100644
--- a/client/Mac/MRDPView.h
+++ b/client/Mac/MRDPView.h
@@ -72,16 +72,6 @@
 
 @end
 
-/* Pointer Flags */
-#define PTR_FLAGS_WHEEL 0x0200
-#define PTR_FLAGS_WHEEL_NEGATIVE 0x0100
-#define PTR_FLAGS_MOVE 0x0800
-#define PTR_FLAGS_DOWN 0x8000
-#define PTR_FLAGS_BUTTON1 0x1000
-#define PTR_FLAGS_BUTTON2 0x2000
-#define PTR_FLAGS_BUTTON3 0x4000
-#define WheelRotationMask 0x01FF
-
 BOOL mac_pre_connect(freerdp *instance);
 BOOL mac_post_connect(freerdp *instance);
 void mac_post_disconnect(freerdp *instance);
diff --git a/client/Mac/MRDPView.m b/client/Mac/MRDPView.m
index 1686c9a71..bb3aaeb9d 100644
--- a/client/Mac/MRDPView.m
+++ b/client/Mac/MRDPView.m
@@ -442,9 +442,10 @@ DWORD WINAPI mac_client_thread(void *param)
 	if (step > 0xFF)
 		step = 0xFF;
 
-	/* Negative rotation, so count down steps from top */
+	/* Negative rotation, so count down steps from top
+	 * 9bit twos complement */
 	if (flags & PTR_FLAGS_WHEEL_NEGATIVE)
-		step = 0xFF - step;
+		step = 0x100 - step;
 
 	mf_scale_mouse_event(context, instance->input, flags | step, 0, 0);
 }
diff --git a/client/Wayland/wlf_input.c b/client/Wayland/wlf_input.c
index b18ec429f..22041eaa2 100644
--- a/client/Wayland/wlf_input.c
+++ b/client/Wayland/wlf_input.c
@@ -178,7 +178,10 @@ BOOL wlf_handle_pointer_axis(freerdp* instance, const UwacPointerAxisEvent* ev)
 	 */
 	for (i = 0; i < abs(direction); i++)
 	{
-		const uint32_t cflags = flags | 0x78;
+		uint32_t cflags = flags | 0x78;
+		/* Convert negative values to 9bit twos complement */
+		if (flags & PTR_FLAGS_WHEEL_NEGATIVE)
+			cflags = (flags & 0xFF00) | (0x100 - (cflags & 0xFF));
 		if (!freerdp_input_send_mouse_event(input, cflags, (UINT16)x, (UINT16)y))
 			return FALSE;
 	}
diff --git a/client/Windows/wf_event.c b/client/Windows/wf_event.c
index 7de3487fb..d1ded4c13 100644
--- a/client/Windows/wf_event.c
+++ b/client/Windows/wf_event.c
@@ -207,7 +207,8 @@ static BOOL wf_event_process_WM_MOUSEWHEEL(wfContext* wfc, HWND hWnd, UINT Msg,
 	if (delta < 0)
 	{
 		flags |= PTR_FLAGS_WHEEL_NEGATIVE;
-		delta = -delta;
+		/* 9bit twos complement, delta already negative */
+		delta = 0x100 + delta;
 	}
 
 	flags |= delta;
diff --git a/client/X11/xf_client.c b/client/X11/xf_client.c
index 0ded63964..e25567f74 100644
--- a/client/X11/xf_client.c
+++ b/client/X11/xf_client.c
@@ -1076,8 +1076,9 @@ static const button_map xf_button_flags[NUM_BUTTONS_MAPPED] = {
 	{ Button2, PTR_FLAGS_BUTTON3 },
 	{ Button3, PTR_FLAGS_BUTTON2 },
 	{ Button4, PTR_FLAGS_WHEEL | 0x78 },
-	{ Button5, PTR_FLAGS_WHEEL | PTR_FLAGS_WHEEL_NEGATIVE | 0x78 },
-	{ 6, PTR_FLAGS_HWHEEL | PTR_FLAGS_WHEEL_NEGATIVE | 0x78 },
+	/* Negative value is 9bit twos complement */
+	{ Button5, PTR_FLAGS_WHEEL | PTR_FLAGS_WHEEL_NEGATIVE | (0x100 - 0x78) },
+	{ 6, PTR_FLAGS_HWHEEL | PTR_FLAGS_WHEEL_NEGATIVE | (0x100 - 0x78) },
 	{ 7, PTR_FLAGS_HWHEEL | 0x78 },
 	{ 8, PTR_XFLAGS_BUTTON1 },
 	{ 9, PTR_XFLAGS_BUTTON2 },