diff --git a/.github/workflows/ci_sanitizer.yml b/.github/workflows/ci_sanitizer.yml
index 58f44f7..b391bf9 100644
--- a/.github/workflows/ci_sanitizer.yml
+++ b/.github/workflows/ci_sanitizer.yml
@@ -15,7 +15,6 @@ concurrency:
 
 env:
   TZ: Europe/Berlin
-  ASAN_OPTIONS: strict_string_checks=1:detect_stack_use_after_return=1:check_initialization_order=1:strict_init_order=1:detect_leaks=1
   TSAN_OPTIONS: ignore_noninstrumented_modules=1
   UBSAN_OPTIONS: print_stacktrace=1
 
@@ -28,6 +27,8 @@ jobs:
     name: ${{ matrix.name }} ${{ matrix.build_type }} ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     if: github.repository_owner == 'seqan' || github.event_name == 'workflow_dispatch'
+    env:
+      ASAN_OPTIONS: strict_string_checks=1:detect_stack_use_after_return=1:check_initialization_order=1:strict_init_order=1:detect_leaks=${{ contains(matrix.os, 'macos') && '0' || '1' }}
     strategy:
       fail-fast: false
       matrix:
diff --git a/test/api/ibfmin_test.cpp b/test/api/ibfmin_test.cpp
index 020448e..6f0d3c4 100644
--- a/test/api/ibfmin_test.cpp
+++ b/test/api/ibfmin_test.cpp
@@ -61,7 +61,7 @@ TEST_F(ibfmin_test, given_expression_thresholds_multiple_threads)
     ibf_args.threads = 2;
     ibf_args.path_out = "IBFMIN_Test_Multiple_";
     std::vector<std::filesystem::path> minimiser_file{};
-    minimiser_file.assign(16, data("mini_example.minimiser"));
+    minimiser_file.assign(128, data("mini_example.minimiser"));
 
     std::vector<uint16_t> expected{1, 2};
 
@@ -73,10 +73,10 @@ TEST_F(ibfmin_test, given_expression_thresholds_multiple_threads)
     load_ibf(ibf, "IBFMIN_Test_Multiple_IBF_1");
     auto agent = ibf.membership_agent();
 
-    std::vector<bool> expected_result(16, 0);
+    std::vector<bool> expected_result(128, 0);
     auto & res = agent.bulk_contains(97);
     EXPECT_RANGE_EQ(expected_result,  res);
-    std::vector<bool> expected_result2(16, 1);
+    std::vector<bool> expected_result2(128, 1);
     auto & res2 = agent.bulk_contains(24);
     EXPECT_RANGE_EQ(expected_result2,  res2);
 }