diff --git a/src/device/device_ledger.cpp b/src/device/device_ledger.cpp
index b7c6fe94d..f83ed1e48 100644
--- a/src/device/device_ledger.cpp
+++ b/src/device/device_ledger.cpp
@@ -695,7 +695,6 @@ namespace hw {
     /* ======================================================================= */
 
     bool device_ledger::derive_subaddress_public_key(const crypto::public_key &pub, const crypto::key_derivation &derivation, const std::size_t output_index, crypto::public_key &derived_pub){
-        AUTO_LOCK_CMD();
         #ifdef DEBUG_HWDEVICE
         const crypto::public_key pub_x = pub;
         crypto::key_derivation derivation_x;
@@ -719,7 +718,7 @@ namespace hw {
         MDEBUG( "derive_subaddress_public_key  : PARSE mode with known viewkey");     
         crypto::derive_subaddress_public_key(pub, derivation, output_index,derived_pub);
       } else {
-       
+        AUTO_LOCK_CMD();
         int offset = set_command_header_noopt(INS_DERIVE_SUBADDRESS_PUBLIC_KEY);
         //pub
         memmove(this->buffer_send+offset, pub.data, 32);
@@ -1059,7 +1058,6 @@ namespace hw {
     }
 
     bool device_ledger::generate_key_derivation(const crypto::public_key &pub, const crypto::secret_key &sec, crypto::key_derivation &derivation) {
-        AUTO_LOCK_CMD();
         bool r = false;
 
         #ifdef DEBUG_HWDEVICE
@@ -1080,6 +1078,7 @@ namespace hw {
         assert(is_fake_view_key(sec));
         r = crypto::generate_key_derivation(pub, this->viewkey, derivation);
       } else {
+        AUTO_LOCK_CMD();
         int offset = set_command_header_noopt(INS_GEN_KEY_DERIVATION);
         //pub
         memmove(this->buffer_send+offset, pub.data, 32);