diff --git a/include/reHDD.h b/include/reHDD.h
index 0dbbda2..eb56a2e 100644
--- a/include/reHDD.h
+++ b/include/reHDD.h
@@ -15,7 +15,7 @@
 #define WORSE_POWERUP 10000  //mark drive if at this limit or beyond
 #define SHRED_ITERATIONS 3U
 #define FROZEN_TIMEOUT 10 //After this timeout (minutes) the drive will be marked as frozen
-#define METRIC_THRESHOLD 3UL*1000UL*1000UL*1000UL //calc shred speed with this minimum of time delta
+#define METRIC_THRESHOLD 3L*1000L*1000L*1000L //calc shred speed with this minimum of time delta
 
 // Logger Settings
 #define LOG_PATH "./reHDD.log"
diff --git a/include/shred.h b/include/shred.h
index 2e34556..f44a32e 100644
--- a/include/shred.h
+++ b/include/shred.h
@@ -17,9 +17,9 @@
 #include <unistd.h>
 #include <string.h>
 
-#define CHUNK_SIZE 1024*1024*2 //amount of bytes that are overwritten at once --> 2MB
-//#define CHUNK_SIZE 1024U*4U //amount of bytes that are overwritten at once
-#define TFNG_DATA_SIZE 65536U //amount of bytes used by tfng
+
+#define CHUNK_SIZE 1024*1024*32 //amount of bytes that are overwritten at once --> 32MB
+#define TFNG_DATA_SIZE CHUNK_SIZE //amount of bytes used by tfng
 
 //#define DEMO_DRIVE_SIZE 1024*1024*256L // 256MB
 //#define DEMO_DRIVE_SIZE 1024*1024*1024L // 1GB