PVS-Studio warning V517 for ReactOS

ULONG
MMixerGetControlTypeFromTopologyNode(IN LPGUID NodeType)
{
  ...
  else if (IsEqualGUIDAligned(NodeType,
                              (LPGUID)&KSNODETYPE_MUX))
  {
    /* mux control */
    return MIXERCONTROL_CONTROLTYPE_MUX;
  }
  else if (IsEqualGUIDAligned(NodeType,
                              (LPGUID)&KSNODETYPE_MUX))
  {
    /* mux control */
    return MIXERCONTROL_CONTROLTYPE_MUX;
  }
  ...
}

This suspicious code was found in ReactOS project by PVS-Studio static code analyzer.
Warning message is:
V517 The use of 'if (A) {...} else if (A) {...}' pattern was detected. There is a probability of logical error presence. Check lines: 177, 182. mmixer filter.c 177

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