diff --git a/src/lib/nbt.cpp b/src/lib/nbt.cpp
index 6a8a329..1c91f35 100644
--- a/src/lib/nbt.cpp
+++ b/src/lib/nbt.cpp
@@ -777,7 +777,7 @@ namespace NBT {
                 return false;
             }
 
-            switch (data[0]) {
+            switch (data[currentPosition]) {
                 case TagType::INT8:
                 case TagType::INT16:
                 case TagType::INT32:
diff --git a/src/lib/nbt.hpp b/src/lib/nbt.hpp
index b473112..b40d804 100644
--- a/src/lib/nbt.hpp
+++ b/src/lib/nbt.hpp
@@ -113,5 +113,5 @@ namespace NBT {
         bool validate(uint8_t data[]);
     };
 
-    bool validateRawNBTData(uint8_t data[], uint64_t dataSize, uint64_t initialPosition, uint64_t* processedDataSize=nullptr);
+    bool validateRawNBTData(uint8_t data[], uint64_t dataSize, uint64_t initialPosition=0, uint64_t* processedDataSize=nullptr);
 }