diff --git a/src/video_display/dummy.cpp b/src/video_display/dummy.cpp
index 5cad8b6bf..d0f71dfe2 100644
--- a/src/video_display/dummy.cpp
+++ b/src/video_display/dummy.cpp
@@ -88,6 +88,7 @@ static auto display_dummy_init(struct module * /* parent */, const char *cfg, un
                                 return nullptr;
                         }
                 } else if (strstr(item, "rgb_shift=") != nullptr) {
+                        item += strlen("rgb_shift=");
                         size_t len;
                         s->rgb_shift[0] = stoi(item, &len);
                         item += len + 1;