diff --git a/armsrc/mifareutil.c b/armsrc/mifareutil.c
index cfd8f4b35..e115e965f 100644
--- a/armsrc/mifareutil.c
+++ b/armsrc/mifareutil.c
@@ -194,7 +194,8 @@ int mifare_classic_authex(struct Crypto1State *pcs, uint32_t uid, uint8_t blockN
     uint32_t save_timeout = iso14a_get_timeout();
 
     // set timeout for authentication response
-    iso14a_set_timeout(106);
+    if (save_timeout > 106)
+        iso14a_set_timeout(106);
 
     // Receive 4 byte tag answer
     len = ReaderReceive(receivedAnswer, receivedAnswerPar);