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+# stream-mixer
+
+<!-- begin:auto-docs -->
+_(no submodules)_
+<!-- end:auto-docs -->
+
+## Purpose
+
+`<StreamMixer>` renders one strip per remote peer, each with a volume range slider, a
+mute toggle, a solo toggle, and a read-only FX-slot-count indicator. The component is
+the visible counterpart to `useStreamMixer()` — both surfaces are required by
+Requirement 6 ("Per-peer stream mixer") and the component's solo button proves the
+DAW-semantics test case from the spec.
+
+Markup is intentionally minimal and unstyled — every interactive control carries an
+`aria-label` derived from the peer id so screen readers announce the right peer, and
+the toggles use `aria-pressed` for accessibility. Consumers who want richer chrome pass
+a `renderStrip` render-prop and own the layout entirely.
+
+## Features
+
+- Default markup with `range` slider, `aria-pressed` mute/solo toggles, FX-slot count.
+- `renderStrip` render-prop for custom layouts (e.g. shadcn cards, drag handles).
+- All mutations route through `useStreamMixer()` — DAW solo semantics inherited
+  unchanged.
+- Group `role="group"` with consumer-supplied `aria-label` for screen readers.
+- Throws `REACT_AUDIO_STREAM.NO_PROVIDER` outside a `<StreamProvider>`.
+
+## Usage: Basic
+
+```tsx
+<StreamMixer label="Live room mix" />
+```
+
+## Usage: Advanced
+
+```tsx
+<StreamMixer
+    label="Studio mix"
+    renderStrip={(peer, { setVolume, setMute, setSolo }) => (
+        <PeerStrip
+            peer={peer}
+            onVolume={setVolume}
+            onMute={() => setMute(!peer.muted)}
+            onSolo={() => setSolo(!peer.soloed)}
+        />
+    )}
+/>
+```
+
+## API Reference
+
+- `StreamMixerProps` — `{ label?: string; renderStrip?: (peer, controls) => ReactNode }`
+- `StreamMixer(props): ReactNode`
+
+## Implementation Notes
+
+The `aria-pressed` attribute is set on both the mute and solo buttons because they are
+two-state toggles — this matches WAI-ARIA's authoring practice for toggle buttons and
+allows assistive tech to announce the current state without parsing the button label.
+The range slider's `value` is bound to the live `peer.volume` so it stays in sync with
+ducking caused by other peers' solo state (per Requirement 6: when any peer is soloed,
+non-soloed peers' track volumes go to 0, and the slider reflects that).