diff --git a/image-extras/common/root/autoprovision-stage1.sh b/image-extras/common/root/autoprovision-stage1.sh
index 501c656..d8d7fc2 100755
--- a/image-extras/common/root/autoprovision-stage1.sh
+++ b/image-extras/common/root/autoprovision-stage1.sh
@@ -41,7 +41,7 @@ setupPendrivePartitions()
 {
     log "Erasing partition table"
     # erase partition table
-    dd if=/dev/zero of=/dev/sda bs=1M count=1
+    dd if=/dev/zero of=/dev/sda bs=1k count=256
 
     rereadPartitionTable