diff --git a/backend/genesys/gl841.cpp b/backend/genesys/gl841.cpp
index 470f9ba..c11a434 100644
--- a/backend/genesys/gl841.cpp
+++ b/backend/genesys/gl841.cpp
@@ -944,7 +944,7 @@ HOME_FREE: 3
         r->value |= REG_0x02_MTRREV;
     }
 
-    gl841_send_slope_table(dev, 3, fast_table.table, 256);
+    gl841_send_slope_table(dev, 3, fast_table.table, 255);
 
     r = sanei_genesys_get_address(reg, 0x67);
     r->value = 0x3f;