diff --git a/extensions/kaldi_align.cpp b/extensions/kaldi_align.cpp
index d82d9e6..7336b7f 100644
--- a/extensions/kaldi_align.cpp
+++ b/extensions/kaldi_align.cpp
@@ -177,7 +177,7 @@ namespace internal {
         const int replications,
         const unsigned int seed)
     {
-        std::default_random_engine rng{seed};
+        std::mt19937 rng{seed};
         std::uniform_int_distribution<> dist{0, static_cast<int>(edit_sym_per_hyp.size()) - 1};
 
         double wer_accum = 0.0, wer_mult_accum = 0.0;
@@ -209,7 +209,7 @@ namespace internal {
         const int replications,
         const unsigned int seed
     ) {
-        std::default_random_engine rng{seed};
+        std::mt19937 rng{seed};
         std::uniform_int_distribution<> dist{0, static_cast<int>(edit_sym_per_hyp.size()) - 1};
 
         double improv_accum = 0.0;
diff --git a/tests/test_align.py b/tests/test_align.py
index 96164b0..1832874 100644
--- a/tests/test_align.py
+++ b/tests/test_align.py
@@ -100,7 +100,7 @@ def test_edit_distance_sclite():
     }
 
 
-approx = partial(pytest.approx, abs=1e-3)
+approx = partial(pytest.approx, abs=3e-3)
 
 
 def test_bootstrap_wer_ci_1system():