diff --git a/src/TEF6686.cpp b/src/TEF6686.cpp
index df09826..93f52f5 100644
--- a/src/TEF6686.cpp
+++ b/src/TEF6686.cpp
@@ -545,7 +545,7 @@ void TEF6686::readRDS(byte showrdserrors)
 
                   bool isValuePresent = false;
                   for (int i = 0; i < 50; i++) {
-                    if (rds.sortaf && (buffer0 == currentfreq) || buffer0 == 0 || af[i].frequency == buffer0) {
+                    if (rds.sortaf && ((buffer0 == currentfreq) || buffer0 == 0 || af[i].frequency == buffer0)) {
                       isValuePresent = true;
                       break;
                     }
@@ -559,7 +559,7 @@ void TEF6686::readRDS(byte showrdserrors)
 
                   isValuePresent = false;
                   for (int i = 0; i < 50; i++) {
-                    if (rds.sortaf && (buffer1 == currentfreq) || buffer1 == 0 || af[i].frequency == buffer1) {
+                    if (rds.sortaf && ((buffer1 == currentfreq) || buffer1 == 0 || af[i].frequency == buffer1)) {
                       isValuePresent = true;
                       break;
                     }