Only check for 2f2f after aes cbc decrypt.

src/meter_iperl.cc

@@ -114,9 +114,6 @@ void MeterIperl::handleTelegram(Telegram *t)
     } else {
         t->content = t->payload;
     }
-    if (t->content[0] != 0x2f || t->content[1] != 0x2f) {
-        warning("(meter_iperl) warning: telegram payload does not start with 2F2F (did you use the correct encryption key?)\n");
-    }
     char log_prefix[256];
     snprintf(log_prefix, 255, "(%s) log", "iperl");
     logTelegram(log_prefix, t->parsed, t->content);

src/wmbus_utils.cc

@@ -126,7 +126,7 @@ void decryptMode5_AES_CBC(Telegram *t, vector<uchar> &aeskey)
     AES_CBC_decrypt_buffer(decrypted_data, content_data, content.size(), &aeskey[0], iv);
 
     if (decrypted_data[0] != 0x2F || decrypted_data[1] != 0x2F) {
-        verbose("(Mode5) decrypt failed!\n");
+        warning("(Mode5) warning: telegram payload does not start with 2F2F (did you use the correct encryption key?)\n");
     }
 
     t->content.clear();