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  <title>reSpeaker XVF3800 flashing — I²S to USB Audio Class</title>
  <desc>Factory firmware is I²S only and never enumerates over USB; flashing the UAC firmware over DFU turns it into a normal USB audio device.</desc>
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  <text class="t nt" x="130" y="106">factory: I²S mode</text>
  <text class="s ns" x="130" y="128">arecord -l shows no capture</text>
  <text class="s ns" x="130" y="146">lsusb missing 2886:…</text>

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  <text class="t bt" x="380" y="106">DFU-flash</text>
  <text class="s bs" x="380" y="128">UAC firmware (v2.0.7)</text>
  <text class="s bs" x="380" y="146">one-time, per board</text>

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  <text class="t gt" x="630" y="106">USB Audio Class 2.0</text>
  <text class="s gs" x="630" y="128">enumerates over USB-C</text>
  <text class="s gs" x="630" y="146">picker finds it normally</text>

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