diff --git a/neode-ui/src/components/cloud/ShareModal.vue b/neode-ui/src/components/cloud/ShareModal.vue
index 34c3d10d..0b845503 100644
--- a/neode-ui/src/components/cloud/ShareModal.vue
+++ b/neode-ui/src/components/cloud/ShareModal.vue
@@ -161,6 +161,57 @@
   </Teleport>
 </template>
 
+<script lang="ts">
+/**
+ * Extension → MIME map used when sharing a file that isn't already in the
+ * catalog (`save()` below, `content.add`). Historically listed exactly four
+ * audio extensions (`mp3`/`flac`/`ogg`/`wav`) and left `m4a`/`aac`/`opus`/
+ * `wma` to fall through to the generic `application/octet-stream` fallback
+ * — those four then never routed to the global audio player (which decides
+ * purely on `mime.startsWith('audio/')`, see `usePaidItemViewer.ts`) and
+ * auto-filed to Documents instead of Music (`content.rs`'s paid-download
+ * auto-filing, same `starts_with("audio/")` check) — 13-CONTEXT.md's
+ * landmine, T-13-72. This fix adds the four missing entries; it does not
+ * change the fallback strategy and does not guess at unknown extensions.
+ *
+ * Kept in sync with two other maps that must agree on every audio
+ * extension (13-11 Task 2's own acceptance criterion):
+ * - `archyContentAdapter.ts`'s `classifyByMime`/`AUDIO_EXT_FALLBACK` (13-06)
+ * - `content.rs`'s auto-filing check (`mime_type.starts_with("audio/")`) —
+ *   that check is prefix-only, so any correct `audio/*` value here already
+ *   agrees with it; the specific `audio/*` strings below are chosen to
+ *   match `classifyByMime`'s own test fixtures exactly, so a byte-for-byte
+ *   MIME string never diverges between the two even though the node-side
+ *   check itself only cares about the prefix.
+ *
+ * Module-scope (not a local const inside `save()`) and exported so it is a
+ * table `archyContentAdapter.test.ts`-style fixture tests can pin directly,
+ * per this task's own `read_first` guidance to follow
+ * `useFileType.test.ts`'s fixture-table convention.
+ */
+export const SHARE_MIME_MAP: Record<string, string> = {
+  jpg: 'image/jpeg',
+  jpeg: 'image/jpeg',
+  png: 'image/png',
+  gif: 'image/gif',
+  webp: 'image/webp',
+  mp4: 'video/mp4',
+  webm: 'video/webm',
+  mkv: 'video/x-matroska',
+  mp3: 'audio/mpeg',
+  flac: 'audio/flac',
+  ogg: 'audio/ogg',
+  wav: 'audio/wav',
+  m4a: 'audio/mp4',
+  aac: 'audio/aac',
+  opus: 'audio/opus',
+  wma: 'audio/x-ms-wma',
+  pdf: 'application/pdf',
+  zip: 'application/zip',
+  txt: 'text/plain',
+}
+</script>
+
 <script setup lang="ts">
 import { ref, onMounted } from 'vue'
 import { rpcClient } from '@/api/rpc-client'
@@ -352,17 +403,11 @@ async function save() {
       // Add if not in catalog
       if (!itemId) {
         const ext = props.filename.split('.').pop()?.toLowerCase() || ''
-        const mimeMap: Record<string, string> = {
-          jpg: 'image/jpeg', jpeg: 'image/jpeg', png: 'image/png', gif: 'image/gif',
-          webp: 'image/webp', mp4: 'video/mp4', webm: 'video/webm', mkv: 'video/x-matroska',
-          mp3: 'audio/mpeg', flac: 'audio/flac', ogg: 'audio/ogg', wav: 'audio/wav',
-          pdf: 'application/pdf', zip: 'application/zip', txt: 'text/plain',
-        }
         const addRes = await rpcClient.call<{ item: { id: string } }>({
           method: 'content.add',
           params: {
             filename: (props.filepath || props.filename).replace(/^\/+/, ''),
-            mime_type: mimeMap[ext] || 'application/octet-stream',
+            mime_type: SHARE_MIME_MAP[ext] || 'application/octet-stream',
             description: '',
           },
         })
diff --git a/neode-ui/src/components/cloud/__tests__/ShareModal.test.ts b/neode-ui/src/components/cloud/__tests__/ShareModal.test.ts
new file mode 100644
index 00000000..55197a0c
--- /dev/null
+++ b/neode-ui/src/components/cloud/__tests__/ShareModal.test.ts
@@ -0,0 +1,73 @@
+import { describe, it, expect } from 'vitest'
+import { SHARE_MIME_MAP } from '../ShareModal.vue'
+
+// 13-11 Task 2: ShareModal.vue's extension-to-MIME map historically listed
+// exactly four audio extensions (mp3/flac/ogg/wav) and left
+// m4a/aac/opus/wma to fall through to `application/octet-stream` — those
+// four never routed to the global audio player and auto-filed to Documents
+// instead of Music. This pins all eight audio extensions plus the existing
+// non-audio entries, following useFileType.test.ts's fixture-table
+// convention.
+
+describe('ShareModal SHARE_MIME_MAP', () => {
+  it.each([
+    ['mp3', 'audio/mpeg'],
+    ['flac', 'audio/flac'],
+    ['ogg', 'audio/ogg'],
+    ['wav', 'audio/wav'],
+    ['m4a', 'audio/mp4'],
+    ['aac', 'audio/aac'],
+    ['opus', 'audio/opus'],
+    ['wma', 'audio/x-ms-wma'],
+  ])('maps .%s to the audio MIME %s', (ext, expected) => {
+    expect(SHARE_MIME_MAP[ext]).toBe(expected)
+  })
+
+  it('every one of the eight audio extensions maps to a real audio/* MIME (not application/octet-stream)', () => {
+    const audioExts = ['mp3', 'flac', 'ogg', 'wav', 'm4a', 'aac', 'opus', 'wma']
+    for (const ext of audioExts) {
+      const mime = SHARE_MIME_MAP[ext]
+      expect(mime).toBeDefined()
+      expect(mime!.startsWith('audio/')).toBe(true)
+    }
+  })
+
+  it('existing non-audio entries are unchanged', () => {
+    expect(SHARE_MIME_MAP.jpg).toBe('image/jpeg')
+    expect(SHARE_MIME_MAP.mp4).toBe('video/mp4')
+    expect(SHARE_MIME_MAP.pdf).toBe('application/pdf')
+    expect(SHARE_MIME_MAP.zip).toBe('application/zip')
+    expect(SHARE_MIME_MAP.txt).toBe('text/plain')
+  })
+
+  it('an unknown extension is absent from the map — the fix adds coverage, it does not guess', () => {
+    expect(SHARE_MIME_MAP.xyz123).toBeUndefined()
+  })
+
+  it('agrees with archyContentAdapter.ts\'s classifyByMime on all eight audio extensions', async () => {
+    const { classifyByMime } = await import('../../../composables/archyContentAdapter')
+    const audioExts = ['mp3', 'flac', 'ogg', 'wav', 'm4a', 'aac', 'opus', 'wma']
+    for (const ext of audioExts) {
+      const mime = SHARE_MIME_MAP[ext]!
+      expect(classifyByMime({ mime_type: mime, filename: `track.${ext}` })).toBe('audio')
+    }
+  })
+})
+
+describe('an audio MIME never opens the lightbox', () => {
+  it('usePaidItemViewer routes every audio/* mime to the global player before its image/video lightbox branch is ever reached', () => {
+    // usePaidItemViewer.ts's routing order is: audio -> global bottom-bar
+    // player (return); image/video -> lightbox (return); anything else ->
+    // browser-tab fallback. The audio branch is checked FIRST and always
+    // returns, so no audio/* mime can ever reach the lightbox branch —
+    // pinned here structurally (mirrors the real predicate, avoids a heavy
+    // component mount) rather than re-implementing usePaidItemViewer's
+    // async RPC/blob flow in a unit test.
+    const audioExts = ['mp3', 'flac', 'ogg', 'wav', 'm4a', 'aac', 'opus', 'wma']
+    for (const ext of audioExts) {
+      const mime = SHARE_MIME_MAP[ext]!
+      const routesToAudioPlayerFirst = mime.startsWith('audio/')
+      expect(routesToAudioPlayerFirst).toBe(true)
+    }
+  })
+})