diff --git a/RX_FSK/src/conn-sdcard.cpp b/RX_FSK/src/conn-sdcard.cpp
index 7c340e1..9aabcc5 100644
--- a/RX_FSK/src/conn-sdcard.cpp
+++ b/RX_FSK/src/conn-sdcard.cpp
@@ -42,7 +42,7 @@ void ConnSDCard::init() {
   Serial.printf("SD card init: %s\n", initok ? "OK" : "Failed");
   uint8_t cardType = SD.cardType();
   Serial.printf("SD Card Type: %s\n", cardTypeStr(cardType));
-  if (cardType == CARD_NONE) { return; }
+  if (cardType == CARD_NONE) { SPI_MUTEX_UNLOCK(); return; }
 
   uint32_t cardSize = SD.cardSize() / (1024 * 1024);
   Serial.printf("SD Card Size: %luMB\n", cardSize);
diff --git a/RX_FSK/version.h b/RX_FSK/version.h
index 3802bef..320d387 100644
--- a/RX_FSK/version.h
+++ b/RX_FSK/version.h
@@ -1,4 +1,4 @@
 const char *version_name = "rdzTTGOsonde";
-const char *version_id = "dev20241222";
+const char *version_id = "dev20241225";
 const int FS_MAJOR=3;
 const int FS_MINOR=3;