diff --git a/src/gfxinit.cpp b/src/gfxinit.cpp
--- a/src/gfxinit.cpp
+++ b/src/gfxinit.cpp
@@ -290,6 +290,8 @@ static bool SwitchNewGRFBlitter()
 	const bool animation_wanted = HasBit(_display_opt, DO_FULL_ANIMATION);
 	const char *cur_blitter = BlitterFactory::GetCurrentBlitter()->GetName();
 
+	VideoDriver::GetInstance()->AcquireBlitterLock();
+
 	for (uint i = 0; i < lengthof(replacement_blitters); i++) {
 		if (animation_wanted && (replacement_blitters[i].animation == 0)) continue;
 		if (!animation_wanted && (replacement_blitters[i].animation == 1)) continue;
@@ -298,7 +300,10 @@ static bool SwitchNewGRFBlitter()
 		if (!IsInsideMM(depth_wanted_by_grf, replacement_blitters[i].min_grf_depth, replacement_blitters[i].max_grf_depth + 1)) continue;
 		const char *repl_blitter = replacement_blitters[i].name;
 
-		if (strcmp(repl_blitter, cur_blitter) == 0) return false;
+		if (strcmp(repl_blitter, cur_blitter) == 0) {
+			VideoDriver::GetInstance()->ReleaseBlitterLock();
+			return false;
+		}
 		if (BlitterFactory::GetBlitterFactory(repl_blitter) == NULL) continue;
 
 		DEBUG(misc, 1, "Switching blitter from '%s' to '%s'... ", cur_blitter, repl_blitter);
@@ -313,6 +318,8 @@ static bool SwitchNewGRFBlitter()
 		if (BlitterFactory::SelectBlitter(cur_blitter) == NULL || !VideoDriver::GetInstance()->AfterBlitterChange()) usererror("Failed to reinitialize video driver. Specify a fixed blitter in the config");
 	}
 
+	VideoDriver::GetInstance()->ReleaseBlitterLock();
+
 	return true;
 }