diff --git a/ci/run.sh b/ci/run.sh
index cbe28442e..b03fdf1c6 100644
--- a/ci/run.sh
+++ b/ci/run.sh
@@ -50,6 +50,10 @@ fi
 
 CMAKE_EXTRA="-DWHISPER_FATAL_WARNINGS=ON"
 
+if [[ "$(uname -m)" == "x86_64" ]]; then
+    CMAKE_EXTRA="${CMAKE_EXTRA} -DGGML_NATIVE=OFF"
+fi
+
 if [ ! -z ${GG_BUILD_METAL} ]; then
     CMAKE_EXTRA="${CMAKE_EXTRA} -DGGML_METAL=ON"
 fi
diff --git a/src/whisper.cpp b/src/whisper.cpp
index 210ca597f..0fe29a454 100644
--- a/src/whisper.cpp
+++ b/src/whisper.cpp
@@ -8258,9 +8258,6 @@ WHISPER_API const char * whisper_bench_ggml_mul_mat_str(int n_threads) {
     // when F16 is used, there is an extra work buffer of size N*N*sizeof(float)
     std::vector<uint8_t> buf(3llu*N_max*N_max*sizeof(float) + 3*ggml_tensor_overhead() + ggml_graph_overhead());
 
-    // put a bunch of random data in the buffer
-    for (size_t i = 0; i < buf.size(); i++) buf[i] = i;
-
     for (int j = 0; j < (int) sizes.size(); j++) {
         int n_q4_0 = 0;
         int n_q4_1 = 0;
@@ -8304,6 +8301,15 @@ WHISPER_API const char * whisper_bench_ggml_mul_mat_str(int n_threads) {
             struct ggml_tensor * a = ggml_new_tensor_2d(ctx0, wtype,         N, N);
             struct ggml_tensor * b = ggml_new_tensor_2d(ctx0, GGML_TYPE_F32, N, N);
 
+            // set tensor data after allocation so previous iteration results don't corrupt it.
+            {
+                uint8_t * a_data = (uint8_t *) a->data;
+                for (size_t ii = 0; ii < ggml_nbytes(a); ii++) a_data[ii] = ii & 0x3F;
+
+                uint8_t * b_data = (uint8_t *) b->data;
+                for (size_t ii = 0; ii < ggml_nbytes(b); ii++) b_data[ii] = ii & 0x3F;
+            }
+
             struct ggml_tensor * c = ggml_mul_mat(ctx0, a, b);
 
             struct ggml_cgraph * gf = ggml_new_graph(ctx0);