diff --git a/firmware/kernel/include/queue.h b/firmware/kernel/include/queue.h
index 6740b88760..a9c3b5a93a 100644
--- a/firmware/kernel/include/queue.h
+++ b/firmware/kernel/include/queue.h
@@ -38,7 +38,7 @@
 /* make sure SYS_EVENT_CLS_BITS has enough range */
 
 /* Bit 31->|S|c...c|i...i| */
-#define SYS_EVENT                 ((long)(int)(1 << 31))
+#define SYS_EVENT                 ((long)(int)(1u << 31))
 #define SYS_EVENT_CLS_BITS        (3)
 #define SYS_EVENT_CLS_SHIFT       (31-SYS_EVENT_CLS_BITS)
 #define SYS_EVENT_CLS_MASK        (((1l << SYS_EVENT_CLS_BITS)-1) << SYS_EVENT_SHIFT)
diff --git a/lib/rbcodec/metadata/metadata_common.h b/lib/rbcodec/metadata/metadata_common.h
index 14115b745a..0f6fcb279c 100644
--- a/lib/rbcodec/metadata/metadata_common.h
+++ b/lib/rbcodec/metadata/metadata_common.h
@@ -30,7 +30,8 @@
 #define TAG_NAME_LENGTH             32
 #define TAG_VALUE_LENGTH            128
 
-#define FOURCC(a,b,c,d) (((a)<<24) | ((b) << 16) | ((c) << 8) | (d))
+#define FOURCC(a,b,c,d) ((((unsigned long)(a)) << 24) | (((unsigned long)(b)) << 16) | \
+                         (((unsigned long)(c)) <<  8) | ((unsigned long)(d)))
 
 enum tagtype { TAGTYPE_APE = 1, TAGTYPE_VORBIS };