diff --git a/src/main/c/src/Transfer.c b/src/main/c/src/Transfer.c
index 0a5e1ac..b613e41 100644
--- a/src/main/c/src/Transfer.c
+++ b/src/main/c/src/Transfer.c
@@ -306,16 +306,23 @@ static void LIBUSB_CALL transferCallback(struct libusb_transfer *transfer)
     // The saved reference to the Java Transfer object.
     jobject jTransfer = transferData->transferObject;
 
-    // Call back into Java.
-    (*env)->CallVoidMethod(env, jCallback, jCallbackMethod, jTransfer);
-
-    // Cleanup Java Transfer object too, if requested.
+    // Read flags before calling the Java method, as it could
+    // free the Transfer itself.
     if (transfer->flags & LIBUSB_TRANSFER_FREE_TRANSFER)
     {
+        // Call back into Java.
+        (*env)->CallVoidMethod(env, jCallback, jCallbackMethod, jTransfer);
+
+        // Cleanup Java Transfer object too, if requested.
         cleanupGlobalReferences(env, jTransfer);
         resetTransfer(env, jTransfer);
         free(transferData);
     }
+    else
+    {
+        // Call back into Java.
+        (*env)->CallVoidMethod(env, jCallback, jCallbackMethod, jTransfer);
+    }
 
     THREAD_END
 }
diff --git a/src/main/resources/de/ailis/usb4java/libusb/linux-x86_64/libusb4java.so b/src/main/resources/de/ailis/usb4java/libusb/linux-x86_64/libusb4java.so
index cb2f9de..2545e37 100644
Binary files a/src/main/resources/de/ailis/usb4java/libusb/linux-x86_64/libusb4java.so and b/src/main/resources/de/ailis/usb4java/libusb/linux-x86_64/libusb4java.so differ
diff --git a/src/main/resources/de/ailis/usb4java/libusb/windows-x86_64/libusb-1.0.dll b/src/main/resources/de/ailis/usb4java/libusb/windows-x86_64/libusb-1.0.dll
index a156868..977eb0c 100644
Binary files a/src/main/resources/de/ailis/usb4java/libusb/windows-x86_64/libusb-1.0.dll and b/src/main/resources/de/ailis/usb4java/libusb/windows-x86_64/libusb-1.0.dll differ
diff --git a/src/main/resources/de/ailis/usb4java/libusb/windows-x86_64/libusb4java.dll b/src/main/resources/de/ailis/usb4java/libusb/windows-x86_64/libusb4java.dll
index 44b9c4b..141fa12 100644
Binary files a/src/main/resources/de/ailis/usb4java/libusb/windows-x86_64/libusb4java.dll and b/src/main/resources/de/ailis/usb4java/libusb/windows-x86_64/libusb4java.dll differ