diff --git a/hi/mkv.c b/hi/mkv.c
index 12a5d6b..795e505 100644
--- a/hi/mkv.c
+++ b/hi/mkv.c
@@ -563,6 +563,7 @@ static int muxmkv_start(CHiPubNode *pubn) {
 	this->fd = fopen(CHi_Crawl(&pubn->sinks[CUTIHI_MUXWEBM_IN_FILENAME])->data.text, "wb");
 	
 	if(!this->fd) {
+		CHi_AddError(pubn, "invalid file", CUTIHI_MUXWEBM_IN_FILENAME);
 		return 0;
 	}
 	
diff --git a/hi/node.c b/hi/node.c
index b3f9517..b1492f0 100644
--- a/hi/node.c
+++ b/hi/node.c
@@ -534,9 +534,7 @@ static int image_perform(CHiPubNode *node) {
 		}
 		
 		if(node->sinks[CUTIHI_IMAGE_IN_FILE].type != CUTIHI_VAL_TEXT) {
-			node->errors.active[0] = true;
-			strncpy(node->errors.code[0], "invalid type", CUTIHI_ERR_SIZE);
-			node->errors.sink[0] = CUTIHI_IMAGE_IN_FILE;
+			CHi_AddError(node, "invalid type", 0);
 			return 1;
 		}
 		
@@ -549,9 +547,7 @@ static int image_perform(CHiPubNode *node) {
 	if(!internal->cacheImg) {
 		struct sail_image *simg;
 		if(sail_load_from_file(fn, &simg) != SAIL_OK) {
-			node->errors.active[0] = true;
-			strncpy(node->errors.code[0], "invalid file", CUTIHI_ERR_SIZE);
-			node->errors.sink[0] = CUTIHI_IMAGE_IN_FILE;
+			CHi_AddError(node, "invalid file", 0);
 			return 1;
 		}
 		
@@ -574,6 +570,9 @@ static int image_perform(CHiPubNode *node) {
 		}
 		
 		sail_destroy_image(cimg);
+		
+		free(internal->cachePath);
+		internal->cachePath = strdup(fn);
 	}
 	
 	if(CHi_Node_Active(node)) {
@@ -717,9 +716,7 @@ static int modulate_perform(CHiPubNode *node) {
 	}
 	
 	if(imgsrc->type != CUTIHI_VAL_SAMPLE) {
-		node->errors.active[0] = true;
-		strncpy(node->errors.code[0], "invalid type", CUTIHI_ERR_SIZE);
-		node->errors.sink[0] = 0;
+		CHi_AddError(node, "invalid type", 0);
 		return 1;
 	}
 	 
@@ -728,11 +725,15 @@ static int modulate_perform(CHiPubNode *node) {
 	
 	if(!CHi_Node_Active(node)) {
 		node->sources->data.sample = NULL;
-		return;
+		return 1;
 	}
 	
 	CHiImage *src = imgsrc->data.sample;
 	
+	if(!src) {
+		return 1;
+	}
+	
 	assert(src->stride % 16 == 0);
 	
 	CHiImage *dst = CHi_Image_New(2, 4, src->stride, src->width, src->height, NULL);
diff --git a/hi/node.h b/hi/node.h
index bcddf8c..0050b09 100644
--- a/hi/node.h
+++ b/hi/node.h
@@ -290,6 +290,9 @@ CUTIVIS CHiValue *CHi_Crawl(CHiValue*);
 CUTIVIS bool CHi_Node_Active(CHiPubNode*);
 
 CUTIVIS void CHi_Node_Destroy(CHiPubNode*);
+
+CUTIVIS void CHi_AddError(CHiPubNode*, const char *err, size_t sink);
+
 #ifdef __cplusplus
 }
 #endif