diff --git a/src/wallet/monero_wallet_full.cpp b/src/wallet/monero_wallet_full.cpp
index 6c98503..7bc1b5a 100644
--- a/src/wallet/monero_wallet_full.cpp
+++ b/src/wallet/monero_wallet_full.cpp
@@ -1583,6 +1583,7 @@ namespace monero {
     }
 
     // scan txs
+    boost::lock_guard<boost::mutex> guarg(m_sync_mutex); // synchronize scanning
     m_w2->scan_tx(tx_hashes);
   }