diff --git a/src/layout/blocked_mul.c b/src/layout/blocked_mul.c
index e9a4944a..c19d65a8 100644
--- a/src/layout/blocked_mul.c
+++ b/src/layout/blocked_mul.c
@@ -28,10 +28,14 @@ void block_update_mul(off_t block_offset, VGMSTREAM * vgmstream) {
         data_header  = 0x00;
         data_size    = 0;
     }
-    if (block_type == 0x00 && block_size != 0) {
+    else if (block_type == 0x00 && block_size != 0) {
         /* read audio sub-header */
         data_size = read_32bit(block_offset + block_header + 0x00,streamFile);
     }
+    else if (block_type < 0) {
+        /* EOF/bad read */
+        data_size = -1;
+    }
     else {
         /* non-audio or empty audio block */
         data_header  = 0x00;