diff --git a/firmware/libcommon/source/sniffer.c b/firmware/libcommon/source/sniffer.c
index 3cd0b89..33c16d3 100644
--- a/firmware/libcommon/source/sniffer.c
+++ b/firmware/libcommon/source/sniffer.c
@@ -215,7 +215,7 @@
 		wt_d = d;
 	}
 	wt = wt_wi*960UL*wt_d;
-	TRACE_INFO("WT updated to %u\n\r", wt);
+	TRACE_INFO("WT updated to %lu\n\r", wt);
 }
 
 /*! Allocate USB buffer and push + initialize simtrace_msg_hdr
@@ -325,7 +325,7 @@
 	uint32_t i;
 	for (i = 0; i < nb_flags; i++) {
 		if (flags & flag_meanings[i].value) {
-			printf(flag_meanings[i].str);
+			printf("%s", flag_meanings[i].str);
 			flags &= ~flag_meanings[i].value;
 			if (flags) {
 				printf(", ");