diff --git a/FlowHelpers/1.0.0/copyWithProgress.js b/FlowHelpers/1.0.0/copyWithProgress.js
index a5c9d8b..fd44026 100644
--- a/FlowHelpers/1.0.0/copyWithProgress.js
+++ b/FlowHelpers/1.0.0/copyWithProgress.js
@@ -2,14 +2,13 @@
 
 const fs = require('fs');
 
-const COPY_BUFFER_SIZE = 4 * 1024 * 1024;
-
 const copyWithProgress = async ({
   source,
   destination,
   jobLog,
   updateProgress,
   label,
+  copyMethod = 'auto',
   maxRetries = 2,
   retryDelayMs = 1000,
 }) => {
@@ -27,16 +26,12 @@ const copyWithProgress = async ({
     if (typeof jobLog === 'function') jobLog(`${message}\n`);
   };
 
-  const copyOnce = () => new Promise((resolve, reject) => {
+  const copyOnceWithStream = () => new Promise((resolve, reject) => {
     const startMs = Date.now();
     let copiedBytes = 0;
     let nextProgressPercent = 0;
-    // Larger buffers avoid issuing thousands of small writes when the
-    // destination is an SMB/CIFS mount with noticeable round-trip latency.
-    const rd = fs.createReadStream(source, { highWaterMark: COPY_BUFFER_SIZE });
-    const wr = fs.createWriteStream(destination, {
-      highWaterMark: COPY_BUFFER_SIZE,
-    });
+    const rd = fs.createReadStream(source, { highWaterMark: 4 * 1024 * 1024 });
+    const wr = fs.createWriteStream(destination, { highWaterMark: 4 * 1024 * 1024 });
     let settled = false;
     const fail = (error) => {
       if (settled) return;
@@ -45,7 +40,6 @@ const copyWithProgress = async ({
       wr.destroy();
       reject(error);
     };
-
     rd.on('error', fail);
     wr.on('error', fail);
     wr.on('finish', () => {
@@ -57,20 +51,45 @@ const copyWithProgress = async ({
       copiedBytes += chunk.length;
       const percent = sourceSize === 0 ? 100 : Math.floor((copiedBytes / sourceSize) * 100);
       if (percent < nextProgressPercent) return;
-
       const elapsedSeconds = Math.max((Date.now() - startMs) / 1000, 0.1);
-      const copiedMb = (copiedBytes / 1024 / 1024).toFixed(1);
-      const speedMbPerSecond = (copiedBytes / 1024 / 1024 / elapsedSeconds).toFixed(1);
       report(
         percent,
         `[${label}] Progress: ${Math.min(percent, 100)}% `
-          + `(${copiedMb}/${sourceSizeMb} MB, ${speedMbPerSecond} MB/s)`,
+          + `(${(copiedBytes / 1024 / 1024).toFixed(1)}/${sourceSizeMb} MB, `
+          + `${(copiedBytes / 1024 / 1024 / elapsedSeconds).toFixed(1)} MB/s)`,
       );
       nextProgressPercent = (Math.floor(percent / 10) + 1) * 10;
     });
     rd.pipe(wr);
   });
 
+  const copyOnceWithNative = () => new Promise((resolve, reject) => {
+    const startMs = Date.now();
+    let settled = false;
+    const progressTimer = setInterval(() => {
+      if (settled || !fs.existsSync(destination)) return;
+      const copiedBytes = fs.statSync(destination).size;
+      const elapsedSeconds = Math.max((Date.now() - startMs) / 1000, 0.1);
+      report(
+        Math.floor((copiedBytes / sourceSize) * 100),
+        `[${label}] Progress: ${Math.min(Math.floor((copiedBytes / sourceSize) * 100), 100)}% `
+          + `(${(copiedBytes / 1024 / 1024).toFixed(1)}/${sourceSizeMb} MB, `
+          + `${(copiedBytes / 1024 / 1024 / elapsedSeconds).toFixed(1)} MB/s)`,
+      );
+    }, 1000);
+    fs.promises.copyFile(source, destination).then(() => {
+      settled = true;
+      clearInterval(progressTimer);
+      resolve(((Date.now() - startMs) / 1000).toFixed(1));
+    }).catch((error) => {
+      settled = true;
+      clearInterval(progressTimer);
+      reject(error);
+    });
+  });
+
+  const copyOnce = copyMethod === 'stream' ? copyOnceWithStream : copyOnceWithNative;
+
   let lastError;
   for (let attempt = 0; attempt <= maxRetries; attempt += 1) {
     if (attempt > 0) {
diff --git a/LocalFlowPlugins/utility/copyToWorkDir/2.0.0/index.js b/LocalFlowPlugins/utility/copyToWorkDir/2.0.0/index.js
index 3c90a43..f53a1c3 100644
--- a/LocalFlowPlugins/utility/copyToWorkDir/2.0.0/index.js
+++ b/LocalFlowPlugins/utility/copyToWorkDir/2.0.0/index.js
@@ -25,6 +25,14 @@ const details = () => ({
       inputUI: { type: 'dropdown', options: ['true', 'false'] },
       tooltip: 'Skip when the source is already inside workDir.',
     },
+    {
+      label: 'Copy method',
+      name: 'copyMethod',
+      type: 'string',
+      defaultValue: 'auto',
+      inputUI: { type: 'dropdown', options: ['auto', 'native', 'stream'] },
+      tooltip: 'Auto uses the operating system copy API; stream is a fallback for problematic mounts.',
+    },
   ],
   outputs: [{ number: 1, tooltip: 'File is ready in workDir — continue to next plugin' }],
 });
@@ -57,6 +65,7 @@ const plugin = async (args) => {
     jobLog,
     updateProgress: args.updateProgress,
     label: 'copyToWorkDir',
+    copyMethod: args.inputs.copyMethod || 'auto',
   });
 
   return {
diff --git a/LocalFlowPlugins/utility/replaceOriginalFile/2.0.0/index.js b/LocalFlowPlugins/utility/replaceOriginalFile/2.0.0/index.js
index 305a75b..0b4602e 100644
--- a/LocalFlowPlugins/utility/replaceOriginalFile/2.0.0/index.js
+++ b/LocalFlowPlugins/utility/replaceOriginalFile/2.0.0/index.js
@@ -25,6 +25,14 @@ const details = () => ({
       inputUI: { type: 'dropdown', options: ['true', 'false'] },
       tooltip: 'Delete the processed file after it has replaced the original.',
     },
+    {
+      label: 'Copy method',
+      name: 'copyMethod',
+      type: 'string',
+      defaultValue: 'auto',
+      inputUI: { type: 'dropdown', options: ['auto', 'native', 'stream'] },
+      tooltip: 'Auto uses the operating system copy API; stream is a fallback for problematic mounts.',
+    },
   ],
   outputs: [{ number: 1, tooltip: 'Original file replaced — continue to next plugin' }],
 });
@@ -62,6 +70,7 @@ const plugin = async (args) => {
       jobLog,
       updateProgress: args.updateProgress,
       label: 'replaceOriginalFile',
+      copyMethod: args.inputs.copyMethod || 'auto',
     });
 
     if (fs.existsSync(destination)) {
diff --git a/README.md b/README.md
index cb4a4e2..f243846 100644
--- a/README.md
+++ b/README.md
@@ -279,8 +279,9 @@ Performs 2-pass libx265 encoding using VBV parameters from `args.variables`.
 
 Streams the source file to the worker's local `workDir`, verifies the byte count,
 reports throttled copy progress, and retries failed writes twice after removing
-the partial destination. It uses large buffered streams for better throughput
-when the library is an SMB/CIFS mount. It stores the original library path in
+the partial destination. Its `Copy method` input defaults to `auto` (the
+operating system's native file-copy path) and offers `stream` as a fallback
+for problematic mounts. It stores the original library path in
 `variables.originalLibraryFile` for `replaceOriginalFile`.
 
 ### 9. `replaceOriginalFile` — Replace Original File
diff --git a/docs/integration-guide.md b/docs/integration-guide.md
index 261eff2..14525ac 100644
--- a/docs/integration-guide.md
+++ b/docs/integration-guide.md
@@ -122,8 +122,9 @@ Aggiungi al PATH di sistema:
 a network share. Place it before the first analysis/transcode node; it records
 the library path for `replaceOriginalFile` 2.0.0.
 Both progress-enabled copy operations verify the destination size and retry
-failed writes twice after removing the partial destination. They use larger
-buffers to avoid slow small-write behavior on SMB/CIFS mounts.
+failed writes twice after removing the partial destination. Their `Copy method`
+input defaults to `auto` (the operating system's native file-copy path), with
+`stream` available as a fallback for problematic SMB/CIFS mounts.
 Both progress-enabled plugins require
 `FlowHelpers/1.0.0/copyWithProgress.js`; the installer downloads it
 automatically.
diff --git a/tests/quick-logic-test.js b/tests/quick-logic-test.js
index e8e8d10..ad3c4bb 100644
--- a/tests/quick-logic-test.js
+++ b/tests/quick-logic-test.js
@@ -222,7 +222,9 @@ const AUDIO_INPUTS = {
   ok(copyHelperCode.includes('maxRetries = 2'), 'copy helper retries failed writes');
   ok(copyHelperCode.includes('Copy size mismatch'), 'copy helper verifies destination size');
   ok(copyHelperCode.includes('fs.unlinkSync(destination)'), 'copy helper removes partial copies before retrying');
-  ok(copyHelperCode.includes('COPY_BUFFER_SIZE = 4 * 1024 * 1024'), 'copy helper uses large SMB-friendly buffers');
+  ok(copyHelperCode.includes('fs.promises.copyFile(source, destination)'), 'copy helper uses native file copying');
+  ok(copyHelperCode.includes("copyMethod = 'auto'"), 'copy helper defaults to automatic copy selection');
+  ok(copyHelperCode.includes("copyMethod === 'stream'"), 'copy helper supports stream fallback');
 
   // ── Summary ───────────────────────────────────────────────────────────────
   console.log(`\n${'='.repeat(55)}`);