diff --git a/src/test/coins_tests.cpp b/src/test/coins_tests.cpp
--- a/src/test/coins_tests.cpp
+++ b/src/test/coins_tests.cpp
@@ -292,6 +292,7 @@
 // overwritten at all cache levels)
 BOOST_AUTO_TEST_CASE(updatecoins_simulation_test) {
     SeedInsecureRand(/* deterministic */ true);
+    g_mock_deterministic_tests = true;
 
     bool spent_a_duplicate_coinbase = false;
     // A simple map to track what we expect the cache stack to represent.
@@ -505,6 +506,8 @@
 
     // Verify coverage.
     BOOST_CHECK(spent_a_duplicate_coinbase);
+
+    g_mock_deterministic_tests = false;
 }
 
 BOOST_AUTO_TEST_CASE(coin_serialization) {