1 files changed, 1 insertions, 1 deletions
diff --git a/mousetsr.c b/mousetsr.c
index cac1808..75fc769 100644
--- a/mousetsr.c
+++ b/mousetsr.c
@@ -768,7 +768,7 @@ static void handle_ps2_packet(void)
 			z = sign_extend(data.ps2_packet[3], 6);
 		} else if (data.ps2_packet[3] & PS2M_IMEX_HORIZONTAL_SCROLL) {
 			// Horizontal scrolling, with 6 bits of precision.
-			z = -sign_extend(data.ps2_packet[3], 6);
+			z = sign_extend(data.ps2_packet[3], 6);
 			wheeln = 1;
 		} else {
 			// Or 2 extra buttons (4, 5)