M src/platform/sdl/gl-main.c → src/platform/sdl/gl-main.c

@@ -74,7 +74,7 @@ context.fname = fname;
 	context.useDebugger = 1;
 	context.renderer = &renderer.d.d;
 	context.frameskip = 0;
-	context.sync.videoFrameWait = 0;
+	context.sync.videoFrameWait = 1;
 	context.sync.audioWait = 1;
 	context.startCallback = _GBASDLStart;
 	context.cleanCallback = _GBASDLClean;
@@ -148,7 +148,9 @@ #else
 			glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, renderer->d.outputBuffer);
 #endif
 			glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
-			glFlush();
+			if (context->sync.videoFrameWait) {
+				glFlush();
+			}
 		}
 		GBASyncWaitFrameEnd(&context->sync);
 		SDL_GL_SwapBuffers();

M src/platform/sdl/sdl-events.c → src/platform/sdl/sdl-events.c

@@ -66,7 +66,8 @@ }
 		break;
 #endif
 	case SDLK_TAB:
-		context->sync.audioWait = !context->sync.audioWait;
+		context->sync.audioWait = event->type != SDL_KEYDOWN;
+		context->sync.videoFrameWait = event->type != SDL_KEYDOWN;
 		return;
 	default:
 		if (event->type == SDL_KEYDOWN) {